Search results for: t-shaped mold.
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 175

Search results for: t-shaped mold.

115 Investigation on the Effect of Sugarcane Bagasse/HDPE Composition on the Screw Withdrawal Resistance of Injection Molded Parts

Authors: Seyed Abdol Mohammad Rezavand, Mohammad Nikbakhsh

Abstract:

Withdrawal resistance of screws driven into HDPE/Sugarcane Bagasse injection molded parts was investigated. After chemical treatment and drying, SCB was pre-mixed with HDPE using twin extruder. The resulting granules are used in producing samples in injection molding machine. SCB with the quantity of %10, %20, and %30 was used. By using a suitable fixture, screw heads can take with tensile test machine grips. Parts with screws in the center and edge were fasten together. Then, withdrawal resistance was measured with tensile test machine. Injection gate is at the one edge of the part. The results show that by increasing SCB content in composite, the withdrawal resistance is decreased. Furthermore, the withdrawal resistance at the edges (near injection gate and the end of the filling path of mold cavity) is more than that of the center.

Keywords: polyethylene, sugarcane bagasse, wood plastic, screw, withdrawal resistance

Procedia PDF Downloads 554
114 Effect of Chemical Treatment on Mechanical Properties of KENAF Fiber Reinforced Unsaturated Polyester Composites

Authors: S. S. Abdullahi, H. Musa, A. A. Salisu, A. Ismaila, A. H. Birniwa

Abstract:

In this study the treated and untreated kenaf fiber reinforced unsaturated polyester conventional composites were prepared. Hand lay-up technique was used with dump-bell shaped mold. The kenaf bast fiber was retted enzymatically, washed, dried and combed with a nylon brush. A portion of the kenaf fiber was mercerized and treated with benzoylchloride prior to composite fabrication. Untreated kenaf fiber was also used to prepare the composites to serve as control. The cured composites were subjected to various mechanical testes, such as hardness test, impact test and tensile strength test. The results obtained indicated an increase in all the parameters tested with the fiber treatment. This is because the lignin, hemi-celluloses, pectin and other impurities were removed during alkaline treatment (i.e mercerization). This shows that, the durability of the natural cellulosic fibers to different composite applications can be achieved via fiber treatments.

Keywords: composite, kenaf fibre, reinforce, retted

Procedia PDF Downloads 490
113 A Study on Optimum Shape in According to Equivalent Stress Distributions at the Die and Plug in the Multi-Pass Drawing Process

Authors: Yeon-Jong Jeong, Mok-Tan Ahn, Seok-Hyeon Park, Seong-Hun Ha, Joon-Hong Park, Jong-Bae Park

Abstract:

Multi-stage drawing process is an important technique for forming a shape that cannot be molded in a single process. multi-stage drawing process in number of passes and the shape of the die are an important factors influencing the productivity and formability of the product. The number and shape of the multi-path in the mold of the drawing process is very influencing the productivity and formability of the product. Half angle of the die and mandrel affects the drawing force and it also affects the completion of the final shape. Thus reducing the number of pass and the die shape optimization are necessary to improve the formability of the billet. Analyzing the load on the die through the FEM analysis and in consideration of the formability of the material presents a die model.

Keywords: multi-pass shape drawing, equivalent stress, FEM, finite element method, optimum shape

Procedia PDF Downloads 448
112 Inverse Dynamics of the Mould Base of Blow Molding Machines

Authors: Vigen Arakelian

Abstract:

This paper deals with the study of devices for displacement of the mould base of blow-molding machines. The displacement of the mould in the studied case is carried out by a linear actuator, which ensures the descent of the mould base and by extension springs, which return the letter in the initial position. The aim of this paper is to study the inverse dynamics of the device for displacement of the mould base of blow-molding machines and to determine its optimum parameters for higher rate of production. In the other words, it is necessary to solve the inverse dynamic problem to find the equation of motion linking applied forces with displacements. This makes it possible to determine the stiffness coefficient of the spring to turn the mold base back to the initial position for a given time. The obtained results are illustrated by a numerical example. It is shown that applying a spring with stiffness returns the mould base of the blow molding machine into the initial position in 0.1 sec.

Keywords: design, mechanisms, dynamics, blow-molding machines

Procedia PDF Downloads 127
111 Multi-Pass Shape Drawing Process Design for Manufacturing of Automotive Reinforcing Agent with Closed Cross-Section Shape using Finite Element Method Analysis

Authors: Mok-Tan Ahn, Hyeok Choi, Joon-Hong Park

Abstract:

Multi-stage drawing process is an important technique for forming a shape that cannot be molded in a single process. multi-stage drawing process in number of passes and the shape of the die are an important factor influencing the productivity and moldability of the product. The number and shape of the multi-path in the mold of the drawing process is very influencing the productivity and moldability of the product. Half angle of the die and mandrel affects the drawing force and it also affects the completion of the final shape. Thus reducing the number of pass and the die shape optimization are necessary to improve the formability of the billet. The purpose of this study, Analyzing the load on the die through the FEM analysis and in consideration of the formability of the material presents a die model.

Keywords: automotive reinforcing agent, multi-pass shape drawing, automotive parts, FEM analysis

Procedia PDF Downloads 428
110 Prediction of Solidification Behavior of Al Alloy in a Cube Mold Cavity

Authors: N. P. Yadav, Deepti Verma

Abstract:

This paper focuses on the mathematical modeling for solidification of Al alloy in a cube mould cavity to study the solidification behavior of casting process. The parametric investigation of solidification process inside the cavity was performed by using computational solidification/melting model coupled with Volume of fluid (VOF) model. The implicit filling algorithm is used in this study to understand the overall process from the filling stage to solidification in a model metal casting process. The model is validated with past studied at same conditions. The solidification process are analyzed by including the effect of pouring velocity and temperature of liquid metal, effect of wall temperature as well natural convection from the wall and geometry of the cavity. These studies show the possibility of various defects during solidification process.

Keywords: buoyancy driven flow, natural convection driven flow, residual flow, secondary flow, volume of fluid

Procedia PDF Downloads 394
109 Molding Properties of Cobalt-Chrome-Based Feedstocks Used in Low-Pressure Powder Injection Molding

Authors: Ehsan Gholami, Vincent Demers

Abstract:

Low-pressure powder injection molding is an emerging technology for cost-effectively producing complex shape metallic parts with the proper dimensional tolerances, either in high or in low production volumes. In this study, the molding properties of cobalt-chrome-based feedstocks were evaluated for use in a low-pressure powder injection molding process. The rheological properties of feedstock formulations were obtained by mixing metallic powder with a proprietary wax-based binder system. Rheological parameters such as reference viscosity, shear rate sensitivity index, and activation energy for viscous flow, were extracted from the viscosity profiles and introduced into the Weir model to calculate the moldability index. Feedstocks were experimentally injected into a spiral mold cavity to validate the injection performance calculated with the model.

Keywords: binder, feedstock, moldability, powder injection molding, viscosity

Procedia PDF Downloads 246
108 Modeling Study of Short Fiber Orientation in Simple Injection Molding Processes

Authors: Ihsane Modhaffar, Kamal Gueraoui, Abouelkacem Qais, Abderrahmane Maaouni, Samir Men-La-Yakhaf, Hamid Eltourroug

Abstract:

The main objective of this paper is to develop a Computational Fluid Dynamics (CFD) model to simulate and characterize the fiber suspension in flow in rectangular cavities. The model is intended to describe the velocity profile and to predict the fiber orientation. The flow was considered to be incompressible, and behave as Newtonian fluid containing suspensions of short-fibers. The numerical model for determination of velocity profile and fiber orientation during mold-filling stage of injection molding process was solved using finite volume method. The governing equations of this problem are: the continuity, the momentum and the energy. The obtained results were compared to available experimental findings. A good agreement between the numerical results and the experimental data was achieved.

Keywords: injection, composites, short-fiber reinforced thermoplastics, fiber orientation, incompressible fluid, numerical simulation

Procedia PDF Downloads 440
107 COVID-19 Impact: How the Pandemic Changed the Fashion Industry

Authors: Akshata Patel, Reenu Singh

Abstract:

This paper focuses on current and upcoming fashion trends and global impact on the fashion industry due to the COVID-19 pandemic. The pandemic has had a major impact on the fashion industry worldwide. At the same time, the fashion market also faces challenges in consumer demand. As the supply chain and distribution channels are interconnected, this outbreak has a global impact due to travel restrictions and raw materials shortages. Given that this particular period represents an unprecedented market situation with almost no prior research on how the industry will recover from such a crisis and mold back to its original form, this research aims to propose new possibilities by evaluating the framework of specific segments. Based on the analysis and extensive literature review, the study develops a conceptual model that will illustrate the various connections among the different segments of the fashion industry. The findings provide actionable considerations for fashion industry pupils when implementing appropriate strategies to prevent unfavourable outcomes during times of crisis, such as the COVID-19 outbreak.

Keywords: COVID-19, fashion industry, global impact, new possibilities, pandemic

Procedia PDF Downloads 247
106 Application of Chitosan as a Natural Antimicrobial Compound in Stirred Yoghurt

Authors: Javad Hesari, Tahereh Donyatalab, Sodeif Azadmard Damirchi, Reza Rezaii Mokaram, Abbas Rafat

Abstract:

The main objective of this research was to increase shelf life of stirred yoghurt by adding chitosan as a naturally antimicrobial compound. Chitosan were added at different concentrations (0.1, 0.3 and 0.6%) to the stirred yoghurt. Samples were stored at refrigerator and room temperature for 3 weeks and tested with respect of microbial properties (counts of starter bacteria, mold and yeast, coliforms and E. coli). Starter bacteria and yeast counts in samples containing chitosan was significantly (p<0.05) lower than those in control samples and its antibacterial and anti-yeast effects increased with increasing concentration of chitosan. The lowest counts of starter bacteria and yeast were observed at samples whit 0.6% of chitosan. The Results showed Chitosan had a positive effect on increasing shelf life and controlling of yeasts and therefore can be used as a natural preservative in stirred yogurt.

Keywords: chitosan, natural preservative, stirred yoghurt, self-life

Procedia PDF Downloads 435
105 Impact of the Xanthan Gum on Rheological Properties of Ceramic Slip

Authors: Souad Hassene Daouadji, Larbi Hammadi, Abdelkrim Hazzab

Abstract:

The slips intended for the manufacture of ceramics must have rheological properties well-defined in order to bring together the qualities required for the casting step (good fluidity for feeding the molds easily settles while generating a regular settling of the dough and for the dehydration phase of the dough in the mold a setting time relatively short is required to have a sufficient refinement which allows demolding both easy and fast). Many additives haveadded in slip of ceramic in order to improve their rheological properties. In this study, we investigated the impact of xanthan gumon rheological properties of ceramic Slip. The modified Cross model is used to fit the stationary flow curves of ceramic slip at different concentration of xanthan added. The thixotropic behavior studied of mixture ceramic slip-xanthan gumat constant temperature is analyzed by using a structural kinetic model (SKM) in order to account for time dependent effect.

Keywords: ceramic slip, xanthan gum, modified cross model, thixotropy, viscosity

Procedia PDF Downloads 153
104 Tribological Characterization of Composites Based on Epoxy Resin Filled with Tailings of Scheelite

Authors: Clarissa D. M. O. Guimaraes, Mariza C. M. Fernandes, Francisco R. V. Diaz, Juliana R. Souza

Abstract:

The use of mineral fillers in the preparation of organic matrix composites can be an efficient alternative in minimizing the environmental damage generated in passive mineral beneficiation processes. In addition, it may represent a new material option for wind, construction, and aeronautical industries, for example. In this sense, epoxy resin composites with Tailings of Scheelite (TS) were developed. The composites were manufactured with 5%, 10% and 20% of TS in volume percentage, homogenized by mechanical mixing and molded in a silicon mold. In order to make the tribological evaluation, pin on disk tests were performed to analyze coefficient of friction and wear. The wear mechanisms were identified by SEM (scanning electron microscope) images. The coefficient of friction had a tendency to decrease with increasing amount of filler. The wear tends to increase with increasing amount of filler, although it exhibits a similar wear behavior. The results suggest characteristics that are potential used in many tribological applications.

Keywords: composites, mineral filler, tailings of scheelite, tribology

Procedia PDF Downloads 140
103 Antifungal Lactobacilli Affect Mycelium Morphology and Protect Apricot Juice against Mold Spoilage

Authors: Nora Laref, Bettache Guessas

Abstract:

Preservation of foods mainly depends on delaying or inhibiting the growth of spoilage microorganisms, and antifungal activity of lactic acid bacteria is one of the technological properties researched. The antifungal activity was screened with overlay method of six strains of lactic acid bacteria (Lactobacillus plantarum LB54, LB52, LB51, LB20, LB24 Lactobacillus farciminis LB53) isolated from silage, camel milk and carrot against Aspergillus sp. Lactobacillus plantarum and farciminis inhibit spore germination and mycelia growth of Aspergillus sp., the production of antifungal compounds by these strains was detectable after 4h of incubation at 30°C and show total inhibition after 24h in liquid media, but in solid media showed a good inhibition after 96h of incubation, these compounds cause malformations in the thalle, conidiophore and conidia. These strains could be used as agents of biopreservation since have the ability to retard Aspergillus sp., growth in apricot juice with and without sugar conserved in refrigerator but not in bread.

Keywords: lactobacillus, antifungal substances, aspergillus, biopreservation

Procedia PDF Downloads 314
102 Cranioplasty with Custom Implant Realized Using 3D Printing Technology

Authors: Trad Khodja Rafik, Mahtout Amine, Ghoul Rachid, Benbouali Amine, Boulahlib Amine, Hariza Abdelmalik

Abstract:

Cranioplasty with custom implant realized using 3D printing technology. Cranioplasty is a surgical act that aims restoring cranial bone losses in order to protect the brain from external aggressions and to improve the patient aesthetic appearance. This objective can be achieved with taking advantage of the current technological development in computer science and biomechanics. The objective of this paper it to present an approach for the realization of high precision biocompatible cranial implants using new 3D printing technologies at the lowest cost. The proposed method is to reproduce the missing part of the skull by referring to its healthy contralateral part. Once the model is validated by the neurosurgeons, a mold is 3D printed for the production of a biocompatible implant in Poly-Methyl-Methacrylate (PMMA) acrylic cement. Using this procedure four patients underwent this procedure with excellent aesthetic results.

Keywords: cranioplasty, cranial bone loss, 3D printing technology, custom-made implants, PMMA

Procedia PDF Downloads 80
101 Using Heat-Mask in the Thermoforming Machine for Component Positioning in Thermoformed Electronics

Authors: Behnam Madadnia

Abstract:

For several years, 3D-shaped electronics have been rising, with many uses in home appliances, automotive, and manufacturing. One of the biggest challenges in the fabrication of 3D shape electronics, which are made by thermoforming, is repeatable and accurate component positioning, and typically there is no control over the final position of the component. This paper aims to address this issue and present a reliable approach for guiding the electronic components in the desired place during thermoforming. We have proposed a heat-control mask in the thermoforming machine to control the heating of the polymer, not allowing specific parts to be formable, which can assure the conductive traces' mechanical stability during thermoforming of the substrate. We have verified our approach's accuracy by applying our method on a real industrial semi-sphere mold for positioning 7 LEDs and one touch sensor. We measured the LEDs' position after thermoforming to prove the process's repeatability. The experiment results demonstrate that the proposed method is capable of positioning electronic components in thermoformed 3D electronics with high precision.

Keywords: 3D-shaped electronics, electronic components, thermoforming, component positioning

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100 Antimicrobial Agents Produced by Yeasts

Authors: T. Büyüksırıt, H. Kuleaşan

Abstract:

Natural antimicrobials are used to preserve foods that can be found in plants, animals, and microorganisms. Antimicrobial substances are natural or artificial agents that produced by microorganisms or obtained semi/total chemical synthesis are used at low concentrations to inhibit the growth of other microorganisms. Food borne pathogens and spoilage microorganisms are inactivated by the use of antagonistic microorganisms and their metabolites. Yeasts can produce toxic proteins or glycoproteins (toxins) that cause inhibition of sensitive bacteria and yeast species. Antimicrobial substance producing phenotypes belonging different yeast genus were isolated from different sources. Toxins secreted by many yeast strains inhibiting the growth of other yeast strains. These strains show antimicrobial activity, inhibiting the growth of mold and bacteria. The effect of antimicrobial agents produced by yeasts can be extremely fast, and therefore may be used in various treatment procedures. Rapid inhibition of microorganisms is possibly caused by microbial cell membrane lipopolysaccharide binding and in activation (neutralization) effect. Antimicrobial agents inhibit the target cells via different mechanisms of action.

Keywords: antimicrobial agents, yeast, toxic protein, glycoprotein

Procedia PDF Downloads 320
99 Optimization of Plastic Injection Molding Parameters by Altering Gate and Runner of Feeding System

Authors: Ali Ramezani

Abstract:

Balancing feeding system of plastic injection molding has overriding importance as it minimizes the process’s product defects such as weld line, shrinkage, sink marks and warpage. This article presents the difference between optimization of feeding system in identical multi-cavity molding and family molding using Moldflow Plastic Insight software. In this work, the effect of dimension, shape, position and type of gates and runners on the products quality was studied. The optimization was carried out by analyzing plastic injection molding process parameters, including melt temperature, mold temperature, cooling time, cooling temperature packing time and packing pressure. It was found that symmetrical feeding system is the most efficient shape for diminishing defects in identical multi-cavity molding. However, the same results were not concluded for family molding due to the differences between volume, mass, thickness and shape of cavities.

Keywords: balancing feeding system, family molding, multi-cavity, Moldflow, plastic injection

Procedia PDF Downloads 102
98 Physicochemical and Microbiological Properties of Kefir, Kefir Yogurt and Chickpea Yogurt

Authors: Nuray Güzeler, Elif Ari, Gözde Konuray, Çağla Özbek

Abstract:

The consumption of functional foods is very common. For this reason, many products which are probiotic, prebiotic, energy reduced and fat reduced are developed. In this research, physicochemical and microbiological properties of functional kefir, kefir yogurt and chickpea yogurt were examined. For this purpose, pH values, titration acidities, viscosity values, water holding capacities, serum separation values, acetaldehyde contents, tyrosine contents, the count of aerobic mesophilic bacteria, lactic acid bacteria count and mold-yeast counts were determined. As a result of performed analysis, the differences between titration acidities, serum separation values, water holding capacities, acetaldehyde and tyrosine contents of samples were statistically significant (p < 0.05). There were no significant differences on pH values, viscosities, and microbiological properties of samples (p > 0.05). Consequently industrial production of functional kefir yogurt and chickpea yogurt may be advised.

Keywords: chickpea yogurt, kefir, kefir yogurt, milk

Procedia PDF Downloads 247
97 Disposable Coffee Cups Recycling

Authors: Sasan Mohammadi

Abstract:

Due to our passion for coffee, we use 16 billion throwaway coffee cups yearly. Coffee lovers throughout the globe have discovered the hard way that their paper cups are not recyclable, despite what coffee businesses have repeatedly assured them [1] A disposable, single-use coffee cup comprises a paper and polyethylene layer. Polyethylene is a typical material used to fill a coffee cup's inside to keep its structure and provide water and heat resistance. In addition, the polyethylene layer prevents recycling since it is difficult to separate the plastic liner from the paper layer [2]. In addition, owing to the plastic membrane lining many of these cups, they cannot be recycled and may take up to 30 years to biodegrade [3]. Most of researcher try to separate plastic part ,but it is not economical and easy.For this purposes,it is not yet happen. In our research we don't separate plastic, just we make a homogeneous pulp with cold water.then fix it in mold and dry it,after completely drying cycle we heated the product in 100 degree of centigrade this cause a sintering effect by plastic particle between paper fibers.This method increase 30 percent the strength of product.This product has a good sound proof and thermal isolation. This means we can use it as insulator.with low density we can control the the density by percentage of air solved in pulp.

Keywords: recycling, disposable coffee cup, insolator, low density

Procedia PDF Downloads 41
96 Isolation and Characterization of Lactic Acid Bacteria from Libyan Traditional Fermented Milk "Laban"

Authors: M. H. Nahaisi, N. M. Almaroum

Abstract:

Laban is a Libyan traditional fermented milk product. This lactic fermentation has been known in many cities of Libya long time ago as stable, nutritious, refreshing drink especially during the summer. 16 naturally fermented milk samples were collected from different cities located in North West of Libya. The average pH, titratable acidity, fat and total solids were 4.16, 0.73%, 1.54% and 8.12 % respectively. Coliform, yeast and mold counts were 21×10⁴, 39×10⁴ and 41 ×10³ cfu/ ml. respectively. The average Lactococcus, Streptococcus, Mesophilic Lactobacillus / Leuconostoc and Thermophilic Lactobacillus counts were 99 ×10⁷, 96 ×10⁷, 93 ×10⁷ and 15 ×10⁷ cfu / ml. respectively. A total of one hundred forty two lactic acid bacteria (LAB) isolates were identified to the genus level as Lactobacillus (48.59%), Lactococcus (43.66%), Streptococcus (4.93%) and Leuconostoc (2.82%). Sugar fermentation tests have revealed that the most frequently Lactobacillus species was found to be Lactobacillus delbrueckii ssp. lactis (62.32%) followed by Lactobacillus plantarum (31.88%). Furthermore, other selected LAB isolates were identified by API 50 CH test as Lactococcus lactis ssp. lactics, Lactobacillus pentosus, Lactobacillus brevis and Leuconostoc mesenteroides ssp. cremoris.

Keywords: traditional fermented milk, laban, lactococcus, streptococcus, mesophilic lactobacillus, thermophilic lactobacillus counts

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95 Plasterwork Ornamentation Finds of Hoşap Castle Archeological Excavation (2007-2015)

Authors: M. Top, H. Telli

Abstract:

Plaster material has been a preferred material especially in the Middle East geography in terms of economy, easy process and thermal insulation since very old times. However, due to the unstable nature of the material, very little has been reached today. For this reason, both finds and studies about stucco ornamentation are very few. In this study, the excavated plasterwork finds used in the architectural ornamentation in the Hosap Castle (Van/Turkey) were considered worth examining since they are rare examples. The stucco relief finds that were found in the castle is discussed. The finds of engraved artifacts on the plasterworks were not addressed. Only the pieces found in Area II and Area III (harem) and surrounding during the cleaning and excavation work carried out at Hosap Kalesi between 2007-2015, will be discussed. This is a general assessment about the finds. It is unknown where many of the pieces found. For this reason, only general appraisal was able to done. Most of the parts are made of mold technique. The motifs on the fragments are similar to the motifs of Ottoman period tiles. Parallel to the settlement history of the castle, thought that these plaster pieces belong to the 16th-17th centuries.

Keywords: stucco decoration, Eastern Anatolia, Ottoman motifs, ornamentation, plasterwork

Procedia PDF Downloads 82
94 The Applications of Wire Print in Composite Material Research and Fabrication Process

Authors: Hsu Yi-Chia, Hoy June-Hao

Abstract:

FDM (Fused Deposition Modeling) is a rapid proofing method without mold, however, high material and time costs have always been a major disadvantage. Wire-printing is the next generation technology that can more flexible, and also easier to apply on a 3D printer and robotic arms printing. It can create its own construction methods. The research is mainly divided into three parts. The first is about the method of parameterizing the generated paths and the conversion of g-code to the wire-printing. The second is about material attempts and the application of effects. Third, is about the improvement of the operation of mechanical equipment and the design of robotic tool-head. The purpose of this study is to develop a new wire-print method that can efficiently generate line segments and paths in three- dimensions space. The parametric modeling software transforms the digital model into a 3D printer or robotic arms g-code, this article uses thermoplastics/ clay/composites materials for testing. The combination of materials and wire-print process makes architects and designers have the ability to research and develop works and construction in the future.

Keywords: parametric software, wire print, robotic arms fabrication, composite filament additive manufacturing

Procedia PDF Downloads 105
93 Thermal and Mechanical Properties of Powder Injection Molded Alumina Nano-Powder

Authors: Mostafa Rezaee Saraji, Ali Keshavarz Panahi

Abstract:

In this work, the processing steps for producing alumina parts using powder injection molding (PIM) technique and nano-powder were investigated and the thermal conductivity and flexural strength of samples were determined as a function of sintering temperature and holding time. In the first step, the feedstock with 58 vol. % of alumina nano-powder with average particle size of 100nm was prepared using Extrumixing method to obtain appropriate homogeneity. This feedstock was injection molded into the two cavity mold with rectangular shape. After injection molding step, thermal and solvent debinding methods were used for debinding of molded samples and then these debinded samples were sintered in different sintering temperatures and holding times. From the results, it was found that the flexural strength and thermal conductivity of samples increased by increasing sintering temperature and holding time; in sintering temperature of 1600ºC and holding time of 5h, the flexural strength and thermal conductivity of sintered samples reached to maximum values of 488MPa and 40.8 W/mK, respectively.

Keywords: alumina nano-powder, thermal conductivity, flexural strength, powder injection molding

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92 Intentional Relationship Building: Stem Faculty Perceptions of Culturally Responsive Mentoring

Authors: Niesha Douglas, Lisa Merriweather, Cathy Howell, Anna Sancyzk

Abstract:

Many studies explain that mentoring in an academic setting contributes to student success and retention. However, in the United States, where the population is diverse and filled with multiple ethnic groups, mentoring has become too generalized and fails to offer a unique individualized experience for underrepresented minorities (URM). The purpose of this paper is to describe the findings of an ongoing qualitative study that investigates the relationships among STEM doctoral faculty and URM students. Several faculty from three different predominately white institutions (PWI) in the Southeastern region of the United States were interviewed and engaged in open dialogue about their experiences with mentoring. The data collection included semi-structured interviews that took place in the classroom (pre-COVID-19) as well as virtually. The theoretical framework draws on the idea of Critical Race Theory and how cultural, social constructs interfere with effective mentoring for URM Doctoral STEM students. The findings in this study suggest that though the faculty and several years of experience mentoring students, there were some gaps in understanding the needs of URM students and how mentoring is a unique relationship that should be specialized for each student and should not fit into one mold.

Keywords: culture, critical race theory, mentoring, STEM

Procedia PDF Downloads 166
91 Solymorph: Design and Fabrication of AI-Driven Kinetic Facades with Soft Robotics for Optimized Building Energy Performance

Authors: Mohammadreza Kashizadeh, Mohammadamin Hashemi

Abstract:

Solymorph, a kinetic building facade designed for optimal energy capture and architectural expression, is explored in this paper. The system integrates photovoltaic panels with soft robotic actuators for precise solar tracking, resulting in enhanced electricity generation compared to static facades. Driven by the growing interest in dynamic building envelopes, the exploration of novel facade systems is necessitated. Increased energy generation and regulation of energy flow within buildings are potential benefits offered by integrating photovoltaic (PV) panels as kinetic elements. However, incorporating these technologies into mainstream architecture presents challenges due to the complexity of coordinating multiple systems. To address this, Solymorph leverages soft robotic actuators, known for their compliance, resilience, and ease of integration. Additionally, the project investigates the potential for employing Large Language Models (LLMs) to streamline the design process. The research methodology involved design development, material selection, component fabrication, and system assembly. Grasshopper (GH) was employed within the digital design environment for parametric modeling and scripting logic, and an LLM was experimented with to generate Python code for the creation of a random surface with user-defined parameters. Various techniques, including casting, 3D printing, and laser cutting, were utilized to fabricate the physical components. Finally, a modular assembly approach was adopted to facilitate installation and maintenance. A case study focusing on the application of Solymorph to an existing library building at Politecnico di Milano is presented. The facade system is divided into sub-frames to optimize solar exposure while maintaining a visually appealing aesthetic. Preliminary structural analyses were conducted using Karamba3D to assess deflection behavior and axial loads within the cable net structure. Additionally, Finite Element (FE) simulations were performed in Abaqus to evaluate the mechanical response of the soft robotic actuators under pneumatic pressure. To validate the design, a physical prototype was created using a mold adapted for a 3D printer's limitations. Casting Silicone Rubber Sil 15 was used for its flexibility and durability. The 3D-printed mold components were assembled, filled with the silicone mixture, and cured. After demolding, nodes and cables were 3D-printed and connected to form the structure, demonstrating the feasibility of the design. Solymorph demonstrates the potential of soft robotics and Artificial Intelligence (AI) for advancements in sustainable building design and construction. The project successfully integrates these technologies to create a dynamic facade system that optimizes energy generation and architectural expression. While limitations exist, Solymorph paves the way for future advancements in energy-efficient facade design. Continued research efforts will focus on cost reduction, improved system performance, and broader applicability.

Keywords: artificial intelligence, energy efficiency, kinetic photovoltaics, pneumatic control, soft robotics, sustainable building

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90 Experimental Study of the Electrical Conductivity and Thermal Conductivity Property of Micro-based Al-Cu-Nb-Mo Alloy

Authors: Uwa C. A., Jamiru T.

Abstract:

Aluminum based alloys with a certain compositional blend and manufacturing method have been reported to have excellent electrical conductors. In the current investigation, metal powders of Aluminum (Al), Copper (Cu), Niobium (Nb), and Molybdenum (Mo) were weighed in accordance with certain ratios and spread equally by combining the powder particles. The metal particles were mixed using a tube mixer for 12 hours. Before pouring into a 30mm-diameter graphite mold, pre-pressed, and placed into an SPS furnace, the thermal conductivity of the mixed metal powders was evaluated using a portable Thermtest device. Axial pressure of 50 MPa was used at a heating rate of 50 oC/min, and a multi-stage heating procedure with a holding period of 10 min. was used to sinter at temperatures between 300 oC and 480 oC. After being cooled to room temperature, the specimens were unmolded to produce the aluminum, copper, niobium, and molybdenum alloy material. The HPS 2662 Precision Four-point Probe Meter was used to determine the electrical resistivity and the values used to calculate the electrical conductivity of the sintered alloy samples. Finally, the alloy with the highest electrical conductivity and thermal conductivity qualities was the one with the following composition: Al 93.5Cu4Nb1.5Mo1. It also had a density of 3.23 g/cm3. It could be advisable for usage in automobile radiator and electric transmission line components.

Keywords: Al-Cu-Nb-Mo, electrical conductivity, alloy, sintering, thermal conductivity

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89 Physical Properties and Elastic Studies of Fluoroaluminate Glasses Based on Alkali

Authors: C. Benhamideche

Abstract:

Fluoroaluminate glasses have been reported as the earliest heavy metal fluoride glasses. By comparison with flurozirconate glasses, they offer a set of similar optical features, but also some differences in their elastic and chemical properties. In practice they have been less developed because their stability against devitrification is smaller than that of the most stable fluoroziconates. The purpose of this study was to investigate glass formation in systems AlF3-YF3-PbF2-MgF2-MF2 (M= Li, Na, K). Synthesis was implemented at room atmosphere using the ammonium fluoride processing. After fining, the liquid was into a preheated brass mold, then annealed below the glass transition temperature for several hours. The samples were polished for optical measurements. Glass formation has been investigated in a systematic way, using pseudo ternary systems in order to allow parameters to vary at the same time. We have chosen the most stable glass compositions for the determination of the physical properties. These properties including characteristic temperatures, density and proprieties elastic. Glass stability increases in multicomponent glasses. Bulk samples have been prepared for physical characterization. These glasses have a potential interest for passive optical fibers because they are less sensitive to water attack than ZBLAN glass, mechanically stronger. It is expected they could have a larger damage threshold for laser power transmission.

Keywords: fluoride glass, aluminium fluoride, thermal properties, density, proprieties elastic

Procedia PDF Downloads 215
88 Simulation and Experimental Research on Pocketing Operation for Toolpath Optimization in CNC Milling

Authors: Rakesh Prajapati, Purvik Patel, Avadhoot Rajurkar

Abstract:

Nowadays, manufacturing industries augment their production lines with modern machining centers backed by CAM software. Several attempts are being made to cut down the programming time for machining complex geometries. Special programs/software have been developed to generate the digital numerical data and to prepare NC programs by using suitable post-processors for different machines. By selecting the tools and manufacturing process then applying tool paths and NC program are generated. More and more complex mechanical parts that earlier were being cast and assembled/manufactured by other processes are now being machined. Majority of these parts require lots of pocketing operations and find their applications in die and mold, turbo machinery, aircraft, nuclear, defense etc. Pocketing operations involve removal of large quantity of material from the metal surface. The modeling of warm cast and clamping a piece of food processing parts which the used of Pro-E and MasterCAM® software. Pocketing operation has been specifically chosen for toolpath optimization. Then after apply Pocketing toolpath, Multi Tool Selection and Reduce Air Time give the results of software simulation time and experimental machining time.

Keywords: toolpath, part program, optimization, pocket

Procedia PDF Downloads 266
87 A Review of Antimicrobial Strategy for Cotton Textile

Authors: C. W. Kan, Y. L. Lam

Abstract:

Cotton textile has large specific surfaces with good adhesion and water-storage properties which provide conditions for the growth and settlement of biological organisms. In addition, the soil, dust and solutes from sweat can also be the sources of nutrients for microorganisms [236]. Generally speaking, algae can grow on textiles under very moist conditions, providing nutrients for fungi and bacteria growth. Fungi cause multiple problems to textiles including discolouration, coloured stains and fibre damage. Bacteria can damage fibre and cause unpleasant odours with a slick and slimy feel. In addition, microbes can disrupt the manufacturing processes such as textile dyeing, printing and finishing operations through the reduction of viscosity, fermentation and mold formation. Therefore, a large demand exists for the anti-microbially finished textiles capable of avoiding or limiting microbial fibre degradation or bio fouling, bacterial incidence, odour generation and spreading or transfer of pathogens. In this review, the main strategy for cotton textile will be reviewed. In the beginning, the classification of bacteria and germs which are commonly found with cotton textiles will be introduced. The chemistry of antimicrobial finishing will be discussed. In addition, the types of antimicrobial treatment will be summarized. Finally, the application and evaluation of antimicrobial treatment on cotton textile will be discussed.

Keywords: antimicrobial, cotton, textile, review

Procedia PDF Downloads 339
86 Effect of Temperature Condition in Extracting Carbon Fibers on Mechanical Properties of Injection Molded Polypropylene Reinforced by Recycled Carbon Fibers

Authors: Shota Nagata, Kazuya Okubo, Toru Fujii

Abstract:

The purpose of this study is to investigate the proper condition in extracting carbon fibers as the reinforcement of composite molded by injection method. Recycled carbon fibers were extracted from wasted CFRP by pyrolyzing epoxy matrix of CFRP under air atmosphere at different temperature conditions 400, 600 and 800°C in this study. Recycled carbon fiber reinforced polypropylene (RCF/PP) pellets were prepared using twin screw extruder. The RCF/PP specimens were molded into dumbbell shaped specimens using injection molding machine. The tensile strength of recycled carbon fiber was decreased with rising pyrolysis temperature from 400 to 800°C. However, superior mechanical properties of tensile strength, tensile modulus and fracture strain of RCF/PP specimen were obtained when the extracting temperature was 600°C. Almost fibers in RCF/PP specimens were aligned in the mold filling direction in this study when the extracting temperature was 600°C. To discuss the results, the failure mechanisms of RCF/PP specimens was shown schematically. Finally, it was concluded that the temperature condition at 600°C should be selected in extracting carbon fibers as the reinforcement of RCF/PP composite molded by injection method.

Keywords: CFRP, recycled carbon fiber, injection molding, mechanical properties, fiber orientation, failure mechanism

Procedia PDF Downloads 411