Mechanical Engineering Materials Research Articles

Grinding-stimulated fluorescence enhancement in carbon nanoparticles/poly(vinyl chloride) composite

The physical damage of engineering materials is challenging to perceive, particularly when they occur with only a slight extent. To present the location of damage to engineering is still difficult to achieve. Mechanical responsive engineering materials are therefore highly desired. Herein, a type of composites comprised of carbon nanoparticles (CNP) and poly(vinyl chloride) (PVC) was prepared via a heating incubation process. Notably, we found that these composites were in a metastable state and exhibited a grinding-stimulated fluorescence enhancement performance. After grinding stimulation, a bright orange-yellow color emission appeared and the fluorescence intensity of the composites exhibited a 75-fold enhancement. It was noted that grinding had no effect on the fluorescence of CNP alone. The fluorescence enhancement may be due to the change in the surface environment of CNP, as grinding facilitates the entry of CNP into PVC. In addition, fluorescence enhancement was also observed in tightening screw experiments using commercialized PVC films, demonstrating the abrasive-stimulated fluorescence enhancement properties of this CNP/PVC. Such remarkable mechanical response property and interesting combination between CNP and PVC will provide avenue to promote the development of smart engineering materials and have considerable potentials in external force response and structure damage surveying.

Vplyv striedavého namáhania na zmenu teploty vzduchu v pružnom pneumatickom elemente

Rubber as a material is one of the frequently used materials in mechanical engineering. This article deals with rubber, or flexible pneumatic elements, the main part of which is rubber. We determine the effect of alternating stress on the temperature change in the flexible pneumatic element under this variable load. We describe a device that serves this purpose. This device was designed and manufactured in our department. We also determine the effect of the air pressure of the flexible element on the temperature of the air and the temperature of the flexible elements. We need to find out the magnitude of these temperatures so that we can determine whether these flexible elements can work without significant negative changes in physical properties.

Laser additive manufactured NiTi-based bioinspired helicoidal structure with excellent pseudoelasticity and energy absorption capacity

Functionality-driven biomimetic additive manufacturing (AM), as a research hotspot of 3D printing field, is providing unprecedented opportunities for developing next-generation functional materials in mechanical, electrical, optical and biomedical engineering. In this work, we developed a laser AM-ed NiTi-based helicoidal structure with excellent pseudoelasticity and energy absorption capacity, inspired by the biological architecture in the exoskeleton of the crab's claw. The rotation angle θ corresponding to the misorientation of rods in adjacent layers, as the key structure parameter, was involved into the investigations on the forming quality, pseudoelastic response and fracture behavior of the laser AM-ed helicoidal structures. The results showed that an increase in θ could improve the forming accuracy of rods but decrease the porosity due to the formation of more closed pores filled with unmelted powder particles. These pores formed by the helically stacked rods had sharp edges that could trigger earlier stress concentration and phase transformation or even strain hardening during the loading process. In views of more uniform stress distribution, the helicoidal structure with θ = 36° exhibited the largest recoverable strain of 4.32 %. Regarding the deformation and fracture behavior, it was found that the helicoidal structures with small θ were inclined to exhibit an auxetic deformation behavior and a sluggish fracture process, while the ones with larger θ were prone to a buckling deformation mode and a sudden failure. Furthermore, all helicoidal structures presented excellent energy absorption properties in terms of both unit volume and unit mass values, which could be attributed to the cross-scale hierarchical structures.

Contribution of Latvian Technical Intelligentsia to Development of Terminology Until the Establishment of the Republic of Latvia

The article considers the development of technical terminology in the Latvian language until the proclamation of the independent state of Latvia in 1918. The activists of the National Awakening became the first creators of technical terminology, describing current technical innovations as, for example, Juris Alunāns (1832–1864) did in 1860 for the telegraph. The need for technical terms became apparent after the Second Baltic Agricultural Exhibition when difficulties arose in describing the showcased exhibits in Latvian. Significant steps in the development of terminology were made on the initiative of student Mikus Skruzītis (also Skruzīšu Mikus; 1861–1905), who suggested collecting frequently used names of parts of various simple devices, and the initiative of Nikolajs Puriņš (also Puriņu Klāvs; 1858–1935) to publish self-education materials in construction («Būvskola» or Building School) and mechanical engineering («Mašīnu būvskola» or Machine Building School). As the proportion of Latvians employed in the industry and the number of persons who received technical education increased, the need to establish organizations that would take care of both technical education in Latvian and the coinage of the necessary terms became more apparent. The Baltic Technical Society (1906) and the Latvian Educational Society (1908), which established their own terminology committees, deserve special recognition. Encyclopaedic dictionaries were also important for the systematization of terminology, especially the conversational dictionary published by the Knowledge Committee of Riga Latvian Society (1903–1921). The research was carried out within the project «Mūsdienu latviešu valodas lietojums un attīstība» (Research on Modern Latvian Language and Development) of the National Research Program of the Latvian Council of Science (No. VPP-LETONIKA-2022/1-0001).

Preface

MAEM (International Conference on Mechanical Automation and Engineering Materials) is an annually held conference for all researchers at home and abroad since 2022, aiming to provide a good platform for scholars and researchers in the field of mechanical automation, engineering materials and related areas to discuss the latest developments and achievements, work out good solutions, and make contributions.The Second International Conference on Mechanical Automation and Engineering Materials (MAEM 2023) was held online from August 2 to 3, 2023 for academic exchanges and discussions.There were over 30 participants from 5 different countries and regions, including China, Russia, Peru and Malaysia, attending MAEM 2023. The conference program was divided into 3 sessions: keynote speeches, oral presentations, and poster presentations. We greatly appreciate Prof. Zhongjun Ding from National Deep Sea Center, China who presided over the conference, and all participants for attending and sharing!We are honored to invite 4 experts to give impressive keynote speeches: Professor Haibo Liu from Dalian University of Technology, China; Prof. Yajun Liu from South China University of Technology, China; Prof. Li Guo from Hunan University, China and Assoc. Prof. Elammaran Jayamani from the Swinburne University of Technology Sarawak Campus, Malaysia.Following the keynote speakers, 3 scholars made oral presentations respectively. And 1 poster presentation came after it. Reporters shared their latest research findings and audiences were actively involved in discussions.We would like to express our gratitude to the reviewers of these manuscripts, who provided their time and expertise to review papers and facilitate the smooth running of MAEM. We are extremely grateful to the organizers, technical program committee, and editors and extend our most sincere thanks to all the authors for their excellent contribution and work and to participants for their active attendance. Our sincere thanks also go to the IOP Publishing editors and managers for their helpful cooperation during the preparation of the proceedings.On behalf of the Organizing Committee of MAEM 2023.List of Technical Program Committee is available in this Pdf.

Сварка деталей из полимерных композиционных материалов на основе термопластов. Ч. 2. Методы сварки деталей из полимерных композиционных материалов на основе термопластов с использованием посторонних источников теплоты

The first article of the cycle was published in № 08-2023 of the journal «Adhesives. Sealants. Technologies». In the second article from the series, the most common thermal methods of the welding of plastic products based on thermoplastics are considered. Welding technologies with the use of extraneous heat sources: heated air, heated tools and melt have been studied in detail. The main parameters of technological modes of welding of the most common thermoplastic materials in mechanical engineering are given.

Calculation Concept for Wood‐Based Components in Mechanical Engineering

Herein, an approach is described for a calculation concept to close the gap between lightweight construction and necessary safety for structural components made of wood materials with use in mechanical engineering. The calculation of wood‐based materials represents a challenge due to the orthotropic material behavior and the many influencing parameters on the mechanical properties. The main objective of the considerations is to predict the mechanical component behavior as precisely as possible. In the next step, the designer can use the results of the calculations to make statements about the component safety. The analyses of this article are part of the joint project “Wood‐based materials in mechanical engineering (HoMaba)”.

PROSES KARBURASI PADAT PADA BAJA KARBON RENDAH DENGAN TEMPERATUR 900 C, 1000 C, DAN 1100 C

This study aims to determine the effect of temperature on the solid carburizing on increasing the hardness value of ST37 steel. This solid carburizing uses temperature variations of 9000C, 10000C and 11000C, with a holding time of 30 minutes. The material used is a mixture of CaCO3 and coconut shell charcoal with mineral water as a cooling medium. The test carried out was the Rockwell hardness test which was carried out in the Mechanical Engineering Materials Testing Lab of Politeknik Negeri Ketapang. From the test results for ST37 steel, the average hardness obtained in the raw material = 48.3 HRB, then in each carbonation treatment at a temperature of 9000C = 48.6 HRB, a temperature of 10000C = 48.9 HRB, a temperature of 11000C = 49.1 HRB. Carburized steel plates with a temperature of 9000C, 10000C and 11000C the test results are harder than the raw material.

Design, Performance Optimization and Application of High-Entropy Alloy Materials in Mechanical Engineering: A Review

High-entropy alloys have multi-scale and complex microstructures, and their properties are highly tunable. They have great potential for development. However, the current development of high-entropy alloys is still dominated by trial and error, lacking effective guidance and low development efficiency. Machine learning is a data-based material design technology, which has been applied to the prediction of phase composition, prediction and optimization of mechanical properties, and auxiliary simulation calculations in the field of high-entropy alloys. However, the insufficiency of existing data, unbalanced distribution and the limitation of the model itself lead to great uncertainty in the composition optimization strategy based on machine learning. Based on this, this paper takes the machine learning method as the core, combines the composition design and the material design idea based on machine learning, and discusses its design idea in the high-entropy alloy system. And summarize their application research status in high entropy alloy composition screening, phase and structure calculation, and performance prediction. Finally, the current problems in this field are proposed, and solutions and future prospects are provided.

The Realization Path of Exploring Ideological and Political Resources in Mechanical Engineering Materials under the New Era's "Great Ideological and Political" Framework

The Realization Path of Exploring Ideological and Political Resources in Mechanical Engineering Materials under the New Era's "Great Ideological and Political" Framework

Teaching ceramic materials in mechanical engineering: An active learning experience

Teaching in higher education is a very demanding task, as students have easy access to information through a computer or mobile device, and nothing seems to surprise them. One of the main concerns of Mechanical Engineering professors is the transmission of the best general competencies and scientific knowledge, and the development of skills that will be very useful in their future professional life in a global employment market. In this way, teachers must continually innovate to motivate students and catch their attention, adopting new teaching methodologies, such as active learning. The main objectives of this teaching methodology are: to provide advanced knowledge in engineering; resolve of engineering problems; experimentation and knowledge discovering and, improvement of soft skills. This paper describes a project entitled “Production of a ceramic component,” included in the Curricular Unit of Non-Metallic Materials, proposed to the students of the third year, the first semester of a Mechanical Engineering course. Each group is assigned a ceramic component and is asked to research and prepare an oral presentation and a poster where they describe all the stages of the manufacturing process. They must consider component requirements, and the scientific and technical details of its production from materials selection to its sale. To carry out this assignment, students must review their basic knowledge of materials science, technical drawing, and materials and manufacture of ceramic components (subjects previously taught in different courses), and search in databases of material properties. Although this assignment is very challenging and time-consuming, students report in informal conversations promoted by teachers that they enjoy it and feel very motivated. They consider that this type of work better prepares them for their future professional life, by improving their soft skills.

Analisa Kekuatan Mekanik Sambungan Las Menggunakan Pola Ayunan Melingkar Dan Zig-Zag Pada Baja Karbon Sedang

Welding is one of the metal joining techniques by melting some of the parent metal and filler metal which is currently widely used with different methods and movements of welding electrodes. These methods aim to obtain flat and smooth welds and at the same time become the impetus for the compilers to conduct research entitled "analysis of the mechanical strength of welded joints using circular and zig-zag swing patterns on medium carbon steel" with the aim of knowing the effect of welding patterns on hardness test on medium carbon steel material and the effect of microstructure welding pattern on medium carbon steel material. This research was conducted in August 2020, at the Mechanical Engineering Materials and Technology Laboratory, Department of Mechanical Engineering, Faculty of Engineering, Halu Oleo University Kendari. The tools used are welding machines, grinding machines, welding goggles, pliers, masks and gloves while the materials are 0.5 cm carbon steel plate, welding electrodes, grinding wheels. The results of the first research are that for welding using a circular electrode movement pattern which shows a softer or more ductile result, while for a harder or brittle result, it is shown in the zigzag electrode movement welding process and secondly that the circular electrode movement in the welding process has an impact on the microstructure. in the HAZ area which is getting darker because the structure formed is dominated by pearlite, while in welding the zigzag electrode movement has an impact on the HAZ area which is getting brighter because it is dominated by the bainite structureKeywords: Circular Welding Pattern, Mechanical Strength, Medium Carbon Steel, Zigzag Welding Pattern,

How to improve superlubricity performance of diketone at steel interface: Effects of oxygen gas

Achievement of steady and reliable super-low friction at the steel/steel contact interface, one of the most tribological systems applied for mechanical moving parts, is of importance for prolonging machine lifetime and reducing energy consumption. Here we reported that the superlubricity performance of the steel/steel sliding interface lubricated with tiny amounts of diketone solution strongly depends on the oxygen content in surrounding environment. The increase of oxygen not only significantly shortens the initial running-in time but also further reduces the stable coefficient of friction in superlubricity stage due to the enhancement of tribochemical reactions. On the one hand, more severe oxidation wear occurring at higher oxygen content facilitates material removal of the contact interface, lowering the contact pressure and the corresponding initial friction. On the other hand, the growth of iron ions during the shear process in high oxygen environment promotes the formation of chelate which acted as an effective lubricated film chemisorbed at the steel/steel friction interface to further lower the interfacial friction. The results provide a new opportunity to further optimize the tribological performance of diketone superlubricity system, especially towards the lubrication of mechanical engineering materials.

RATIONAL CONDITIONS FOR ULTRASONIC STABILIZATION OF RESIDUAL STRESSES IN ROUND PLATES

In modern conditions of a market economy, the problem of improving the quality of products and ensuring their competitiveness for the countries of the Eurasian Economic Union is becoming the most urgent. The solution of existing problems is aimed at the development of processing methods based on the use of ultrasonic energy. The use of ultrasound makes it possible to increase the scientific and technical level of technological processes for processing parts from hard-to-process materials in mechanical engineering, and in some cases, to solve technological problems of their production in a fundamentally new way. (Research purpose) The research purpose is the optimization of the processing mode of round elastic plates, widely used in various automatic devices in order to stabilize residual stresses in their material. (Materials and methods) One of the most important requirements for such products is the exact match of the deformation value of the plate and the measured pressure of the medium. This is not always ensured due to the emerging phenomenon of elastic static hysteresis, as a result part of the energy spent on deformation of the plate is absorbed by the plate material and a so-called hysteresis loop is formed. This leads to a significant loss of accuracy of measuring instruments. (Results and discussion) The article presents the main stages of the process of choosing stabilization conditions: describing the tasks of ultrasonic vibromechanical processing; justification of the criterion for describing conditions; identification of statistical parameters characterizing the initial state of the part; mathematical modeling of the potential energy of residual stresses in the part; modeling the relaxation process of residual stresses in the part. (Conclusions) The theoretical foundations of a new microdynamic method allows correcting deviations of geometric shape, removing residual stresses and stabilizing the geometric parameters of round plates.

МНОГОФУНКЦИОНАЛЬНАЯ МАГНИТНО - ИМПУЛЬСНАЯ УСТАНОВКА С ИЗМЕНЯЕМОЙ ФОРМОЙ И ПАРАМЕТРАМИ РАЗРЯДНОГО ТОКА

The paper considers methods and circuitry for creating a multifunctional pulse-magnetic installation with variable parameters of the discharge current for forming of pulsed magnetic fields. The installation is designed to conduct comprehensive research on the effect of the magnetic field on various materials in mechanical engineering, medicine, pharmacology and plant growing. Currently, traditional designs of the installations operate in a single-discharge mode and generate oscillatory shaped pulses of current in the form of a damped sinusoid. The developed installation with power intensity of 5 kJ operates in four modes: oscillatory discharge of one energy storage device with a high frequency of the discharge current, synchronous discharge of two energy storage devices, asynchronous discharge of two storage devices with an adjustable delay relative to each other, and in the mode of forming a mono-pulse with a cutoff of the current of subsequent half-cycles. The paper presents the block diagram of the multifunctional pulse-magnetic installation (PMI), provides recommendations on the selection of the main components when creating specialized installations for solving specific tasks. The results of testing the PMI are given.

Building Virtual Laboratory with Simulations

AbstractThis paper describes an innovative approach to modernizing a sophomore mechanical engineering materials course by employing simulations. The three‐credit course includes a lecture and a lab. In the lecture, students learn about theories of material formation and material properties, and in the lab, experiments are conducted to test the strength of materials in response to mechanical forces. A new module comprising simulation assignments has recently been integrated into the course. Having added this module, it is now feasible to simultaneously harness the power of simulations for predicting results of material testing, and provide a virtual lab that can be easily deployed when necessary. The main goal is to assist students with the learning process. Students gain a deeper understanding of the material properties and the changes resulting from various testing procedures by simulating the influence of relevant parameters and using visualizations. The other goal is to familiarize students with modern computational tools for solving engineering problems. The significance of this approach is in using industrial software early in the curriculum, and helping fulfill the Accreditation Board for Engineering and Technology Criterion 3 outcomes 1, 3, and 6. Students are also required to compare their simulation results with the experimental data and discuss the potential sources of variations. The objective is to improve students' critical skills and decision making in design problems.

Comparison of Effect of Orientation on SS304 and SS316 Material Samples Fabricated with DMLS Technology

SS316 and SS304 are most widely used materials in mechanical engineering. Many times the products are subjected to tensile load during work. The knowledge of tensile properties is essential for the mechanical engineer working with materials. SS304 and SS316 samples were fabricated using Direct Metal Laser Sintering (DMLS) as per JIS standards in different orientations. The samples were then tested for their tensile strength. The same has been simulated on the NX platform for prediction of variations in the tensile strength with change in orientation. The results obtained from the simulation are observed to be in good agreement with the experiment results when the process parameters are same in both the cases. Further, the simulation has been used to predict the tensile strength of the samples that were not experimented.

Automated System for Complex Non-Destructive Testing of the Structure and Mechanical Properties of Mechanical Engineering Materials

Automated System for Complex Non-Destructive Testing of the Structure and Mechanical Properties of Mechanical Engineering Materials

Автоматизированная система комплексного неразрушающего контроля структуры и механических свойств материалов машиностроения

An automated system with two optimized modular devices is presented — MULTITEST-MC010 for research of ferromagnetic materials with the methods for measuring magnetic noise and magneto acoustic emission of Barkhausen and MULTITEST — CD010 for research of mechanical engineering materials with the methods of velocity measurement of longitudinal waves C and attenuation coefficient δof ultrasound. The main approaches and principles for the automated data processing of complex non-destructive testing are presented, as well as the setup of the modular devices of the automated system. For approbation of the system the influence of the heat treatment (hardness) in structural steel 40X on the non-destructive information parameters of the magnetic noise and the magneto acoustic emission — magnetic noise voltage EBN and voltage of the magneto acoustic emission EMAE was studied. The mechanical properties in foundry cast iron samples with complex measurement of the information parameters , C, by simultaneous use of the two modular devices of the system were also studied. The possibility for the complex application of these parameters for non-destructive testing of the mechanical properties after heat treatment in structural steel 40X and the tensile strength in cast iron specimens has been proven.

Linear Relationship Between Carbohydrates & Sugar Intake Amount and Incremental PPG Amount via Engineering Strength of Materials using GHMethod: Math-Physical Medicine, Part 1 (No. 346)

This article is a special research on the linear elasticity behavior of glucose using his defined GH-modulus (or M2) to link the input of carbs/sugar intake amount and output of incremental PPG amount. Here is the formula he used in his previously published papers: Predicted PPG= (FPG* 0.97) + (carbs/sugar grams * M2) - (post-meal waking K-steps * 5) He has connected this biomedical equation with a basic concept of stress and strain, along with the Young’s modulus of strength of materials in structural and mechanical engineering. Using his collected 11,580 data of glucose, food, and exercise, he has demonstrated that a “pseudo-linear” relationship indeed existing between the carbs/sugar intake amount multiplied with a “GH modulus (i.e. M2)”, which is similar to the “stress” on an engineering system; and the incremental PPG amount, which is similar to the “strain” of an engineering system. A newly defined coefficient of “GH-modulus” as the value of M2 multiplier is similar to the Young’s modules of stress-strain relationship in the subject of engineering strength of materials. This investigation has proven the existing pseudo-linear relationship between food as stress on the liver and incremental glucose as strain from the liver, particularly during his better controlled period of diabetes from 7/1/2015 to 10/13/2020. This article is a special research on the linear elasticity of glucose with his defined GH-modulus (or M2) and engineering modeling methodologies to investigate various biomedical problems. This methodology and approach are resulted from his specific academic background and different professional experiences prior to his medical research work beginning in 2010. Therefore, he has been trying to link his newly acquired biomedical knowledge over the past decade with his previously acquired mathematics, physics, computer science, and engineering knowledge over 40 years. The human body is the most complex system he has dealt with. However, by applying his previous acquired knowledge to his newly found interest of medicine, he can discover many hidden facts or truths inside the biomedical systems. Many basic concepts, theoretical frame of thoughts, and practical modeling techniques from his fondamental disciplines in the past can be applied to his medical research endeavor. After all, science is based on theory via creation and proof via evidence, and as long as we can discover hidden truths, it does not matter which method we use and which way we take. This is the foundation of the GH-Method: math-physics medicine.