Shape and volume optimization of industrial parts

In the present time, there are many challenges in the production of industrial parts. Due to the constantly rising prices of materials and energy, it is necessary to constantly look for ways to optimize production costs and optimize material consumption. There is great pressure on economical production, i. to produce products with the lowest costs given the expected and necessary properties. With the introduction of additive manufacturing technologies into practice and the production of parts for end use comes the introduction of methods for optimizing the shape of the part and the required amount of material for its production. We call this method Topological Optimization. The presented article describes the preparation of topologically optimized parts and a comparison of their strength properties with respect to the original and the original part.

Mathematical Modeling of the Process of Reduction of the Material Consumption of Gas Transmission System Elements

The new method for a comprehensive assessment of the strength, durability and material capacity of the critical elements of the main gas pipelines, taking into account the combined impact of factors causing damage (environment, corrosion, random loading, geometry variation, material defects, etc.), which are changing the bearing capacity and material capacity of these structures, is proposed. As the main damaging factor, the process of corrosion fatigue is accepted, the qualitative and quantitative assessment of which are realized by applying a set of equations of comparable fatigue lines obtained by fatigue tests carried out in air and in corrosive environment. By the joint solution of these equations, the functions of the corrosion action coefficients are obtained in a wide range of cyclic strength and durability, which in standard calculation procedures are performed only for cyclic strength and only at the inflection point of the fatigue lines (NG 5  106 cycles).The issues of reducing the material consumption and ensuring the cost-effectiveness of structures, by using relatively cheap materials for pipelines - low-carbon and low-alloy structural steels subjected to surface hardening in stressed sections of pipes (edge welds) in order to significantly increase the physical and mechanical characteristics of the used steel grades are considered. In order to increase the corrosion resistance of these sections, contemporary polymer anticorrosive coatings are used.

Tool Bits with Elastic Damping Inserted Elements Formed by Semi-Inserts with Different Rigidity

Vibration during turning is a consequence of premature tool wear and an increase in the roughness of parts. The designs of tool bits that increase their durability, reduce vibrations arising during the cutting process, and improve the quality of processing are of practical and scientific interest. Existing developments of vibration-damping bits with elastic damping inserts of constant rigidity, in which a holder or mandrel with a cut-off insert is installed, do not meet the requirements for the efficiency of vibration reduction due to the impossibility of the necessary vibration damping; the consumption of insert materials is high. Innovative designs of tool bits with inserts formed by semi-inserts with different rigidity are proposed, which allows improving the quality of processing by increasing the efficiency of vibration damping, reducing material consumption, because the length of the semi-inserts is less than half the length of the full insert. The tool bits can be used in the area of cutting materials, mechanical engineering and tool manufacturing.

Do Materialistic Consumers Buy More During the COVID-19 Pandemic?

This study investigates the mediated moderating relationship of self-concept clarity, materialism, and social consumption motivation in the context of Covid-19 pandemic based on the terror management theory. The findings suggest that Malaysian consumers have high self-concept clarity about their materialistic orientation. This materialistic orientation may be of hedonistic-utilitarian nature that is internally directed for self-satisfaction and not exclusively directed externally in material consumption to portray an image to others. Furthermore, this study posits that cultural factors like collectivism and uncertainty avoidance delimits the applicability of terror management theory in Malaysia, suggesting that the development of the theory draw heavily from Western ideology of individualism not directly relevant in the Asian context. Finally, this study offers an understanding of the self-concept clarity from the Asian context, addressing the the appeal by Dunlop (2017) to investigate the construct of self-concept clarity particularly in non-Western context.

The Resource and Leagile Strategy Model for Apparel Export Enterprises

Apparel export enterprises are organizations that are part of the global supply chain. Covid-19, a global pandemic, has emerged as a supply chain disruption since March 2020. The situation is uncertain, and export enterprises at upstream need clear visibility to manage business activities at their end. Due to Covid-19, all global chain stakeholders are at risk, but the apparel chain upstream is more vulnerable than in developing and underdeveloped countries. The situation is exacerbating sustainability and causing labor jobs, excess inventory, production waste, and irresponsible raw material consumption. The paper aims to propose a model based on resource capabilities and a supply chain strategy for exporting enterprises. The model presented in the research is the 'Resource & Leagile Strategy' (RLS) model. The study uses the resource-based view (RBV) to specify resources and leagile strategy to manage the uncertainties created due to Covid-19.

Study of GeSn (0.524 eV) Single-Junction Thermophotovoltaic Cells Based on Device Transport Model

Based on the transport equation of the semiconductor device model for 0.524 eV GeSn alloy and the experimental parameters of the material, thermal-electricity conversion performance governed by GeSn diode has been systematically studied in its normal and inverted structure. For the normal p+/n (n+/p) structure, it is demonstrated here that an optimal base doping N d(a) = 3 (7)×1018 cm-3 is observed, and the superior p+/n structure can reach the higher performance. To reduce material consumption, an economical active layer can be comprised of 100-300 nm emitter and 3-6 μm base to attain comparable performance as that for the optimal configuration. The results can offer many useful guidelines for the fabrication of economical GeSn thermophotovoltaic devices.

FABRICATION CYCLES COMPARISON OF ASSEMBLIES AND MONOLITHIC PARTS MADE BY 3D PRINTING METHOD

The article presents an analysis of the time-consuming, energy-consuming, and cost-consuming nature of 3D printing a three-dimensional polymer components made in two separate approaches: assembly and monolith structure of various materials (automatic filament change required). The introduction includes the definition of 3D printing, its advantages and examples of practical applications, as well as the reason for undertaking the researches described in the article. The justification of the form of 3D sample models was discussed in detail, as well as the methodology adopted by the authors for comparing the print characteristics and the steps of the printing cycles (print preparation, the course of the printing process and post-processing). A comparison of the materials consumption in the phasess of manual and automatic filament change in the mixer were also described. The test printout was made on the Prusa i3 MK3S printer for filament deposition (FDM or FFF methods). For automatic filament mixing, the Palette 2 Pro device was used. The conclusions also include guidelines for the design and production of models made in one continuous printing cycle (using automatic filament feeding devices). Monolithic elements are less accurate, while elements with replaceable filaments are cheaper, less energy-consuming and the material consumption is lower.