Sintering of Biomaterials for Arthroplasty: A Comparative Study of Microwave and Conventional Sintering Techniques

2019 ◽  
Vol 895 ◽  
pp. 83-89 ◽  
Author(s):  
Shivani Gupta ◽  
Apurbba Kumar Sharma
Keyword(s):  
Energy Efficient ◽  
Manufacturing Industry ◽  
Raw Materials ◽  
Microwave Sintering ◽  
High Strength ◽  
Working Environment ◽  
Process Efficiency ◽  
World Population ◽  
Time Saving ◽  
Conventional Sintering

The serious diseases and accidents are the leading causes for the surgeries/transplantation in human body. In present time, a large proportion of world population is facing arthritis problems that lead to partial/total knee arthroplasty and total hip arthroplasty. The implants used in the arthroplasty require high strength, high corrosion and wear resistance and longer life span in a working environment. The quality of fabricated implants significantly depends upon the manufacturing methods used to process the raw materials. In present time, various sintering techniques are popularly used to produced implants owing to improved product quality; however, artificial implant manufacturing industry is looking for more energy efficient, time saving and eco-friendly processing techniques which can offer implants at economical cost along with adequate quality. The present article reviews an overview of different sintering techniques used for producing biomedical implants have been presented. The limitations of these processes have been highlighted and the potential of microwave sintering to address these challenges has been identified. Advantages of using microwave sintering over conventional sintering are also discussed in terms of microstructures, mechanical properties and process efficiency. It has been realized that microwave sintering has potential to cater the needs of the industry for processing of biomaterials as a time saving, energy efficient and environment friendly sintering technique as compare to conventional sintering.

scholarly journals Facile preparation of high conductive silver electrodes by dip-coating followed by quick sintering

2020 ◽  
Vol 7 (1) ◽  
pp. 191571 ◽  
Author(s):  
Tianrui Chen ◽  
Hui Yang ◽  
Shengchi Bai ◽  
Yan Zhang ◽  
Xingzhong Guo
Keyword(s):  
Surface Roughness ◽  
Raw Materials ◽  
Microwave Sintering ◽  
Dip Coating ◽  
Sintering Process ◽  
Silver Films ◽  
Conventional Sintering ◽  
Coating Method ◽  
Silver Electrodes ◽  
Dip Coating Method

With polyol-synthesized silver nanoparticles (AgNPs) as raw materials, the silver electrodes with high conductivity were fabricated via a dip-coating method followed by sintering process, and the effects of the dip-coating and sintering process on the conductivity and surface roughness of silver electrodes were investigated in detail. The silver film with a thickness of 1.97 µm and a roughness of about 2 nm can be prepared after dip-coating at a pulling rate of 500 µm s −1 for 40 coating times. The non-conductive dip-coated silver films are transformed into conductive silver electrodes after conventional sintering in a muffle oven, infrared sintering and microwave sintering, respectively. Compared with high sintering temperature and long sintering time of conventional sintering and infrared sintering, microwave sintering can achieve quick sintering of silver films to fabricate high conductive silver electrodes. The silver electrodes with a sheet resistance of 0.75 Ω sq −1 and a surface roughness of less than 1 nm can be obtained after microwave sintering at 500 W for 50 s. The adjustable dip-coating method followed by quick microware sintering is an appropriate approach to prepare high conductive AgNPs-based electrodes for organic light-emitting diodes or other devices.

The Integration of New Technology Research on Composite Inorganic Fiber Acoustic Insulation Spray in Engineering Construction

2014 ◽  
Vol 580-583 ◽  
pp. 2239-2243
Author(s):  
Jun Yi Shao ◽  
Dong Wang
Keyword(s):  
Energy Efficient ◽  
Raw Materials ◽  
New Technology ◽  
High Strength ◽  
Technology Research ◽  
Insulating Layer ◽  
Building Roof ◽  
Engineering Construction ◽  
Key Technology ◽  
Acoustic Insulation

Composite inorganic fiber spray technology was based on high-strength interfacial agent, then sprayed an appropriate mixed proportion of ultrafine diameter (D <4μm) composite inorganic fibers, adhesives, cement and other raw materials through a dedicated spray equipment on the building roof (ceiling) or flank, which formed a homogeneous, porous, durable and eco-friendly cover layer. The key technology is combined composite inorganic fiber sprays’ adhesive, mixing, porous, insulation and acoustic fireproof mechanism with three key technology working principles " high-strength interfacial agent sector coverage ", " composite inorganic fibers + adhesive multiple mixed spray " and " continuous overall seamless fireproof insulating layer ", to achieve integrate engineering effects of insulation, fastness, energy-efficient, sound-absorbing and homogeneous coverage. The new technology solves acoustic insulation problems of public buildings with fireproof requirements as: underground garage ceiling, elevator shafts and fire passage, etc.

Bamboo Waste-based Bio-composite Substance: An application for Low-cost Construction Materials

2020 ◽  
Vol 4 (1) ◽  
pp. 41-48
Author(s):  
Teodoro Astorga Amatosa ◽  
Michael E. Loretero
Keyword(s):  
Composite Materials ◽  
Sea Water ◽  
Raw Materials ◽  
Low Cost ◽  
Construction Materials ◽  
Single Layer ◽  
High Strength ◽  
Green Technology ◽  
Experimental Medium ◽  
Natural Treatment

Bamboo is a lightweight and high-strength raw materials that encouraged researchers to investigate and explore, especially in the field of biocomposite and declared as one of the green-technology on the environment as fully accountable as eco-products. This research was to assess the technical feasibility of making single-layer experimental Medium-Density Particleboard panels from the bamboo waste of a three-year-old (Dendrocalamus asper). Waste materials were performed to produce composite materials using epoxy resin (C21H25C105) from a natural treatment by soaking with an average of pH 7.6 level of sea-water. Three different types of MDP produced, i.e., bamboo waste strip MDP (SMDP), bamboo waste chips MDP (CMDP) and bamboo waste mixed strip-chips MDP (MMDP) by following the same process. The experimental panels tested for their physical-mechanical properties according to the procedures defined by ASTM D1037-12. Conclusively, even the present study shows properties of MDP with higher and comparable to other composite materials; further research must be given better attention as potential substitute to be used as hardwood materials, especially in the production, design, and construction usage.

scholarly journals Tenebrio molitor in the circular economy: a novel approach for plastic valorisation and PHA biological recovery

2021 ◽  
Author(s):  
Paola Sangiorgio ◽  
Alessandra Verardi ◽  
Salvatore Dimatteo ◽  
Anna Spagnoletta ◽  
Stefania Moliterni ◽  
...  
Keyword(s):  
Circular Economy ◽  
Raw Materials ◽  
Economic Value ◽  
Tenebrio Molitor ◽  
World Population ◽  
Plastic Pollution ◽  
Biological Recovery ◽  
Great Opportunity ◽  
Novel Approach ◽  
The One

AbstractThe increase in the world population leads to rising demand and consumption of plastic raw materials; only a small percentage of plastics is recovered and recycled, increasing the quantity of waste released into the environment and losing its economic value. The plastics represent a great opportunity in the circular perspective of their reuse and recycling. Research is moving, on the one hand, to implement sustainable systems for plastic waste management and on the other to find new non-fossil-based plastics such as polyhydroxyalkanoates (PHAs). In this review, we focus our attention on Tenebrio molitor (TM) as a valuable solution for plastic biodegradation and biological recovery of new biopolymers (e.g. PHA) from plastic-producing microorganisms, exploiting its highly diversified gut microbiota. TM’s use for plastic pollution management is controversial. However, TM microbiota is recognised as a source of plastic-degrading microorganisms. TM-based plastic degradation is improved by co-feeding with food loss and waste as a dietary energy source, thus valorising these low-value substrates in a circular economy perspective. TM as a bioreactor is a valid alternative to traditional PHA recovery systems with the advantage of obtaining, in addition to highly pure PHA, protein biomass and rearing waste from which to produce fertilisers, chitin/chitosan, biochar and biodiesel. Finally, we describe the critical aspects of these TM-based approaches, mainly related to TM mass production, eventual food safety problems, possible release of microplastics and lack of dedicated legislation.

Improving Efficiency of Apparel Manufacturing Through the Principles of Resource Management

2021 ◽  
pp. 0887302X2110054
Author(s):  
Anis Fatima ◽  
Muhammad Tufail
Keyword(s):  
Resource Management ◽  
Competitive Advantage ◽  
Manufacturing Industry ◽  
Apparel Industry ◽  
Process Efficiency ◽  
Apparel Manufacturing ◽  
Effective Utilization ◽  
Time Motion ◽  
Motion Study ◽  
Product Layout

To gain the competitive advantage, it has become essential for manufacturing industry to use its resources effectively, efficiently and economically. It is required to understand that such resources are based on 5 Ms (manpower, methods, materials, money, and machinery). In this study an apparel industry was selected to create a directorial plan by using the ideologies of resource management to improve the process efficiency. For this the data related to the product layout, operation plan, and process flow was collected. Time motion study was performed for aspect analysis. Information regarding operation, number of machines and efficiency of the production line was evaluated. The proposed plan successfully increase the efficiency up to 10%. It also shows an improvement in effective utilization of manpower and money.

scholarly journals Can We Use Grip Strength to Predict Other Types of Hand Exertions? An Example of Manufacturing Industry Workers

2021 ◽  
Vol 18 (3) ◽  
pp. 856
Author(s):  
Victor Ei-Wen Lo ◽  
Yi-Chen Chiu ◽  
Hsin-Hung Tu
Keyword(s):  
Grip Strength ◽  
Manufacturing Industry ◽  
Prediction Models ◽  
Demographic Variable ◽  
Time Saving ◽  
Daily Lives ◽  
Working Environments ◽  
Central Taiwan ◽  
Study Participants ◽  
The Relationship

Background: There are different types of hand motions in people’s daily lives and working environments. However, testing duration increases as the types of hand motions increase to build a normative database. Long testing duration decreases the motivation of study participants. The purpose of this study is to propose models to predict pinch and press strength using grip strength. Methods: One hundred ninety-eight healthy volunteers were recruited from the manufacturing industries in Central Taiwan. The five types of hand motions were grip, lateral pinch, palmar pinch, thumb press, and ball of thumb press. Stepwise multiple linear regression was used to explore the relationship between force type, gender, height, weight, age, and muscle strength. Results: The prediction models developed according to the variable of the strength of the opposite hand are good for explaining variance (76.9–93.1%). Gender is the key demographic variable in the predicting models. Grip strength is not a good predictor of palmar pinch (adjusted-R2: 0.572–0.609), nor of thumb press and ball of thumb (adjusted-R2: 0.279–0.443). Conclusions: We recommend measuring the palmar pinch and ball of thumb strength and using them to predict the other two hand motions for convenience and time saving.

scholarly journals Design of Low-Cost and High-Strength Titanium Alloys Using Pseudo-Spinodal Mechanism through Diffusion Couple Technology and CALPHAD

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2910
Author(s):  
Chaoyi Ding ◽  
Chun Liu ◽  
Ligang Zhang ◽  
Di Wu ◽  
Libin Liu
Keyword(s):  
Diffusion Couple ◽  
Titanium Alloys ◽  
High Throughput ◽  
Volume Fraction ◽  
Raw Materials ◽  
Low Cost ◽  
High Strength ◽  
High Yield ◽  
Α Phase ◽  
Cr System

The high cost of development and raw materials have been obstacles to the widespread use of titanium alloys. In the present study, the high-throughput experimental method of diffusion couple combined with CALPHAD calculation was used to design and prepare the low-cost and high-strength Ti-Al-Cr system titanium alloy. The results showed that ultra-fine α phase was obtained in Ti-6Al-10.9Cr alloy designed through the pseudo-spinodal mechanism, and it has a high yield strength of 1437 ± 7 MPa. Furthermore, application of the 3D strength model of Ti-6Al-xCr alloy showed that the strength of the alloy depended on the volume fraction and thickness of the α phase. The large number of α/β interfaces produced by ultra-fine α phase greatly improved the strength of the alloy but limited its ductility. Thus, we have demonstrated that the pseudo-spinodal mechanism combined with high-throughput diffusion couple technology and CALPHAD was an efficient method to design low-cost and high-strength titanium alloys.

C80 Early Strength Micro Expansion of Steel Tube Reinforced Concrete Research

2015 ◽  
Vol 1119 ◽  
pp. 752-755
Author(s):  
Chang Zheng Sun ◽  
Zheng Wang
Keyword(s):  
High Performance ◽  
Raw Materials ◽  
Influence Factors ◽  
High Strength ◽  
Steel Tube ◽  
Strength Analysis ◽  
Self Compacting Concrete ◽  
Mix Proportion ◽  
Early Strength ◽  
Working Performance

Optimization of mix proportion parameter ，Using ordinary raw materials makes a C80 high performance self-compacting concrete;By joining a homemade perceptual expansion agent, significantly improve the early strength of concrete and effective to solve the high strength of self-compacting concrete caused by gelled material consumption big contraction;Further study on the working performance of high-strength self-compacting concrete, age strength, analysis the influence factors of concrete are discussed.

Integrated Process for Textile Cotton Waste (TCW) Valorization: Waste-to-Energy and Wastewater Decontamination

2016 ◽  
Author(s):  
A. Ribeiro ◽  
C. Vilarinho ◽  
J. Araújo ◽  
J. Carvalho
Keyword(s):  
Raw Materials ◽  
Removal Rate ◽  
Low Cost ◽  
Calorific Value ◽  
Waste To Energy ◽  
Synthetic Wastewater ◽  
Small Scale ◽  
World Population ◽  
Cotton Waste ◽  
Textile Industries

The increasing of world population, industrialization and global consuming, existing market products existed in the along with diversification of raw materials, are responsible for an exponential increase of wastes. This scenario represents loss of resources and ultimately causes air, soils and water pollution. Therefore, proper waste management is currently one of the major challenges faced by modern societies. Textile industries represents, in Portugal, almost 10% of total productive transforming sector and 19% of total employments in the sector composed by almost 7.000 companies. One of the main environmental problems of textile industries is the production of significant quantities of wastes from its different processing steps. According to the Portuguese Institute of Statistics (INE) these industries produce almost 500.000 tons of wastes each year, with the textile cotton waste (TCW) being the most expressive. It was estimated that 4.000 tons of TCW are produced each year in Portugal. In this work an integrated TCW valorisation procedure was evaluated, firstly by its thermal and energetic valorisation with slow pyrolysis followed by the utilization of biochar by-product, in lead and chromium synthetic wastewater decontamination. Pyrolysis experiments were conducted in a small scale rotating pyrolysis reactor with 0.1 m3 of total capacity. Results of pyrolysis experiments showed the formation of 0,241 m3 of biogas for each kilogram of TCW. Results also demonstrated that the biogas is mostly composed by hydrogen (22%), methane (14 %), carbon monoxide (20%) and carbon dioxide (12%), which represents a total high calorific value of 12.3 MJ/Nm3. Regarding biochar, results of elemental analysis demonstrated a high percentage of carbon driving its use as low cost adsorbent. Adsorption experiments were conducted with lead and chromium synthetic wastewaters (25, 50 and 100 mg L−1) in batch vessels with controlled pH. It was evaluated the behaviour of adsorption capacity and removal rate of each metal during 120 minutes of contact time using 5, 10 and 50 g L−1 of adsorbent dosage. Results indicated high affinity of adsorbent with each tested metal with 78% of removal rate in chromium and 95% in lead experiments. This suggests that biochar from TCW pyrolysis may be appropriated to wastewaters treatment, with high contents of heavy metals and it can be an effective alternative to activated carbon.

Application of Combined Casting-Forging Process for Production of Durable Lightweight Aluminum Parts

2013 ◽  
Vol 554-557 ◽  
pp. 264-273 ◽  
Author(s):  
Stanislav Dedov ◽  
Gunter Lehmann ◽  
Rudolf Kawalla
Keyword(s):  
Heat Treatment ◽  
High Performance ◽  
High Strength ◽  
High Energy ◽  
Process Efficiency ◽  
Light Weight ◽  
Technological Chain ◽  
Process Chains ◽  
Coupled Process ◽  
Hardening Heat Treatment

Due to the constant development in the automotive industry, where high performance shared with the maximal comfort and safety at low car body weight are the primary goals, gains the lightweight construction in importance. Materials with light weight, high strength and toughness are being engaged. With this background the material aluminum and its alloys become highly attractive to manufacturers. There are mainly two ways of forming the metal materials: casting or forming. Apart from substitution of one method by another there are also many examples of combining of casting and forging processes in practice. Such approach allows using the advantages of both methods, shortening the process chains and saving energy and resources at the same time. Furthermore the form flexibility can be increased and the product quality can be improved. For higher process efficiency a direct transition from casting to forging operation should be applied, so that the heat loss decreases and no additional heat treatment between these operations is necessary. There are processes known, which allow producing the final parts by casting and forging from one a single heat. The application of such processes requires materials, which have simultaneously good casting and forging properties. The Institute of Metal forming TU Freiberg works intensively on development of combined casting-forging technologies for lightweight aluminum parts. A technological chain for this coupled process followed by precipitation hardening heat treatment was developed (Figure 1). Heat treatable aluminum cast and wrought alloys with 1 – 7 % silicon were applied. By the variation of silicon content the optimal cast, forging and hardening properties were achieved. This technology with high energy efficiency allows producing durable light weight parts from aluminum alloys while the mechanical properties of the final parts are equal to or even higher than those in the conventional processes.

Sign in / Sign up

Export Citation Format

Share Document