1,720,997 research outputs found
Performance improvement of Al-alloyed materials via plasma spray coating
No full textPurpose - The aim of the research is to increase piston and engine performance by using ceramic coated pistons instead of pistons which are manufactured from aluminum alloys and having a coated flame chamber. Design/methodology/approach - Thermal torch and thermal shock tests were performed on the pistons and some specimens of 1.5 mm thick were prepared according to ASTM standards; both have the same material characteristics. In the present work, plasma spray technique was used for ceramic coating. Findings - It was found that the ceramic coating, which, when performed properly, has compatible expansion coefficient with the aluminum alloy pistons, increases performance of pistons and engines. Research limitations/implications - Coatings were limited with one type of bonding and two ceramics, and coated parts were subjected to thermal torch and thermal shock tests. Practical implications - For future work, instead of using other coating materials, stable yttria is used as the best coating material with optimum thermal resistance. By this process, working life of the machine parts can be extended and a number of economical advantages may also be obtained. Originality/value - This paper fulfils the identified information and offers practical help to the industrial firms working with ceramic coatings and also to the academicians working on wear of materials
Cutting tools and applications
Full text linkCutting tools are one of the basic elements of modern industrial production, providing high efficiency and precision in machining different materials. This article examines the basic materials such as high-speed steels, stellites, hard metals and cermets, which are frequently used in cutting tool technologies, and their applications in machining processes. High speed steels (HSS) are preferred in a wide range of applications due to their superior wear resistance and impact resistance. These steels, enhanced with alloying elements such as carbon, vanadium and molybdenum, are widely used in machine tools operating at low speeds. Stellites are generally cobalt-based alloys that stand out with their high hardness and corrosion resistance. These materials are preferred in special applications by maintaining wear resistance even at high temperatures. Hard metals consist of components such as tungsten carbide (WC) and offer excellent performance at high cutting speeds. These materials are widely used in sectors requiring precision machining such as automotive and aerospace. Cermets are a combination of ceramic and metal phases and combine high hardness with chemical stability. It is especially preferred in applications where fine stock removal and surface quality are important. As a result, each cutting tool material offers specific advantages and limitations depending on the application requirements. The right material selection optimizes tool life and workpiece surface quality while increasing production efficiency
Forensic materials and test methods
Full text linkIn recent years, forensic engineering, a growing field of engineering, has developed. If the product malfunctions prematurely, the user will not be able to use that product, and sometimes it may lead to personal injuries. Sophisticated techniques such as SEM and DSC are used to study these problems. Forensic engineers evaluate documentary evidence so that the court can make the right decision. In this study, forensic materials and test methods are discussed. For this purpose, first, the concept of Forensic Engineering was introduced and the defects occurring in the products were examined. Then, in case of a dispute between the parties, it is explained how forensic engineers examine the products and prepare an expert report to resolve the dispute. Finally, how and with which devices macroscopic and microscopic tests, mechanical and thermal tests were performed were examined
Nanomaterials and their applications
Full text linkThe word nano takes its meaning from the Greek word "nanos" which means dwarf. Nanoparticles are materials ranging in size between 1 and 100 nanometers. A nanometer is one billionth of a meter. Nanotechnology is an interdisciplinary field that researches the physical, chemical and biological structures of materials with dimensions of one billionth and deals with their usage areas. Nanomaterials are the cornerstones of nanotechnology and they possess unique optical, magnetic and electrical properties in this dimension. What makes nanotechnology so interesting is that materials behave differently from the macro world in this dimension. Power / weight ratio, conductivity, optical and magnetic properties change significantly as we move from macro dimension to nanosize. In this study, after giving general information about nanomaterials, nanotechnology processes, imaging techniques of nanomaterials, carbon nanotubes, nanocomposites, nanotechnology in nature and various nanotechnology applications have been investigated
Particulate composites, analysis techniques and applications
Full text linkThe combination of at least two of the metal, ceramic or polymer groups at a macro level is called a composite material and, in this way, better properties are obtained. Composites can be partitioned into three groupings as layered, fiber and particle reinforced. Particulate composites offer flexibility in composition and component design and are isotropic. This investigation critically examines analysis techniques for particulate composites such as dimensional measurements, property distribution, composition and phase tests, density, and porosity tests (e.g. Archimedes, Pycnometer), hardness measurements (e.g. Brinell, Rockwell), mechanical properties through non-destructive and destructive testing (e.g. tensile, impact). In addition, application areas of particulate composites are highlighted, including Al-SiC composites for aircrafts, cemented carbides for tool metals, dental porcelain, electrical contacts, friction products, and thermal materials
Nanostructures and applications
Full text linkNanotechnology is an interdisciplinary area that studies materials and structures of billionths in size and their uses. Nanomaterials are the keystones of nanotechnology and have exclusive electrical, magnetic and optical properties. What makes nanotechnology so stimulating is that materials perform contrarily in this dimension than in the macro world. The weight/power proportion, magnetic and optical possessions as well as conductivity alter meaningfully as you change from the macro dimension to the nano dimension. In this investigation, after giving overall data about nanomaterials, nanosystems, nanomachines, nanorobots and nanosystems from nanostructures were examined. Then, from nanostructure applications to the automotive industry, energy. defense and environmental applications were examined. Finally, nanofuture for nanostructures is discussed
Selection of materials for camshafts
Full text linkSurface hardening heat treatment is applied to make the interior of the part softer, but the exterior harder and more wear-resistant. This surface hardening method is particularly useful in power-transmitting parts such as camshafts or ring gears where a hard outer surface is required. Surface hardening processes are divided into thermochemical processes (changing the composition of the surface with carbon, nitrogen and boron) and rapid quenching from the austenite area to form martensite. In this study, materials selection for camshafts is reviewed and candidates from cast irons and steels are criticized and classical and computer-based methods are employed for the best selection
Recent developments of metallic implants for biomedical applications
Full text linkMedical implants have undoubtedly made an indelible mark on our world during the last century. More than 100 million humans carry at least one major internal medical device. The prosthesis industry has topped 50 billion US$ in annual sales, with approximately 150 universities throughout the world proposing an undergraduate program in bioengineering or biomedical engineering. Despite that, however, most medical devices have been constructed using a significantly restricted number of conventional metallic, ceramic, polymeric, and composite biomaterials. In this study, recent developments of metallic implants are summarized for biomedical applications. To do this, first desired properties for biomaterials are defined. Then, types of metallic biomaterials are classified as stainless steel, Mg, Co, Ti, nobble and biodegradable ones. After that, surface modifications are defined for corrugation, topographies and chemical modification. Finally, future perspective is outlined for the sake of development new materials as well as production point of view. 
Sustainable composite materials: Applications and future
Full text linkSustainable composite materials represent a critical step towards a more environmentally friendly future. They are an alternative to traditional composites by reducing waste. Sustainability of materials can be achieved through various studies. Composite materials will become more efficient and environmentally friendly with the various findings of researchers. They will play an important role in overcoming challenges such as resource scarcity. Sustainable composites significantly decrease environmental problems related to the production of biodegradable engineered materials. The production of sustainable composites results in less energy consumption and lower toxic gases. Sustainable composites are used in packaging, construction, automobiles, sports, and furniture equipment. In this study, sustainable composite materials are examined and criticized considering their benefits, innovations, applications and challenges, and future perspectives
Materials selection and case studies
Full text linkIn the most general sense, everything that people need is called a material. In a specific sense, we can say that all kinds of tools and equipment that engineers use to produce are called materials. Materials Science studies the various properties of materials such as mechanical and physical; It is also a branch of science that deals with their application to various scientific and technological fields and is in the interest of almost every technical staff member. A technical staff member who does not have sufficient knowledge about the structure and properties of the materials cannot choose the most suitable material for his usage area. Errors can reach large dimensions; this can put the choice of the material and other relevant units in a difficult situation. Understanding materials has led to progress in design since ancient times. The process of replacing old materials with new ones has occurred from time to time, as there is so much material today than before. The importance of material selection as part of the design process is growing, especially due to industrial competition. Therefore, design and material engineering and scientists are in close relationship for the design and selection of economical materials that will best respond to the desired service conditions. More than 200 thousand materials used in the industry are used. These materials should be selected in accordance with their usage areas. If the materials are chosen incorrectly, this causes loss of life and property. In this study, diagrams used in material selection are introduced and 3 examples are given on the subject
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