Development Of Powder Metallurgy Research Articles

Nitrogen alloyed austenitic Ni-free stainless steel for additive manufacturing

Nitrogen alloyed austenitic nickel-free stainless steel (ANFSS) is one of the most promising group of materials for consumer and healthcare products. They can be used to substitute not only conventional AISI 316L, but also more expensive titanium and Co-Cr alloys. Previously the utilization of nitrogen alloyed materials has been limited due to poor machinability resulting from high strength and ductility, and difficulties in manufacturing the nitrogen alloyed raw materials. Recent developments in powder metallurgy, for example, additive manufacturing (AM), offer feasible net shape manufacturing routes to go around machining and material related challenges. The present study investigates and introduces a viable processing route for an ANFSS by gas atomization, direct energy deposition (DED), and sintering. Special attention is paid to control the nitrogen content in different processing steps by investigating a Fe-16Mn-14Cr-0.27C-0.35N alloy with experimental and computational methods. The results show that the nitrogen content can be computationally estimated and maintained at desired level by proper selection of processing parameters, and thereby controlling the final nitrogen content of the ANFSS alloy.

Theoretical Aspects of Production of Products by Hot Isostatic Pressing

The role of powder metallurgy in the modern world is increasing every year. The introduction of new technologies in powder metallurgy contributes to the successful solution of complex problems in creating parts that have completely new, progressive properties. The development of powder metallurgy is mainly because its technological operations are relatively simple, and the effect achieved with their help in many cases is striking. One of the most promising methods for forming powder materials is the hot isostatic pressing method. This method allows the manufacture of materials and products with special compositions, structure and properties. However, to ensure the necessary characteristics and to eliminate defects in the finished product, it is necessary to strictly observe all technological operations of hot isostatic pressing.

ACOUSTIC PERFORMANCES OF METAL SAMPLES MANUFACTURED BY ADDITIVE TECHNOLOGIES

Porous materials (PMs) have been widely used since the development of powder metallurgy. PM samples are obtained by various methods, while the structure varies from sample to sample. Deviation from a given structure leads to a deviation of the specified properties up to 30%, including acoustic. Selective laser melting (SLM), allows to obtain samples with a low structural deviation (up to 13%) in a wide porosity range P=0.3-0.7. An increase in the sound absorption coefficient and the expansion of the frequency range allows to use such samples in noise reduction units’ designs. Nine samples with different porosity and cell shape were obtained by the SLM method with the use of AlSi10Mg aluminum powder obtained by gas atomization and BB751P nickel powder obtained by plasma centrifugal spraying. The porosity of the samples (P) varied in the range (0.3–0.7), the diameter was D = 34.5 mm, and the height varied in the range of 15–45 mm. The acoustic characteristics comparison of traditional PMs with porous fused material (PFM) by the sound absorption index shows that PM, as a rule, are superior to PFM, while it is approximately equal to porous cast

Current trends in the development of powder metallurgy: design and production of heat-resistant alloys

Current trends in the development of powder metallurgy: design and production of heat-resistant alloys

New development of powder metallurgy in automotive industry

The driving force for using powder metallurgy (PM) mostly relies on its near net-shape ability and cost-performance ratio. The automotive application is a main market of PM industry, requiring parts with competitive mechanical or functional performance in a mass production scale. As the automobile technology transforms from traditional internal combustion engine vehicles to new energy vehicles, PM technology is undergoing significant changes in manufacturing and materials development. This review outlines the challenges and opportunities generated by the changes in the automotive technology for PM. Low-cost, high-performance and light-weight are critical aspects for future PM materials development. Therefore, the studies on PM lean-alloyed steel, aluminum alloys, and titanium alloy materials were reviewed. In addition, PM soft magnetic composite applied to new energy vehicles was discussed. Then new opportunities for advanced processing, such as metal injection molding (MIM) and additive manufacturing (AM), in automotive industry were stated. In general, the change in automotive industry raises sufficient development space for PM. While, emerging technologies require more preeminent PM materials. Iron-based parts are still the main PM products due to their mechanical performance and low cost. MIM will occupy the growing market of highly flexible and complex parts. AM opens a door for fast prototyping, great flexibility and customizing at low cost, driving weight and assembling reduction.

Recent developments in powder metallurgy based aluminium alloy composite for aerospace applications

Abstract Aluminium and its alloys (AA) offers greater potential for weight reduction in automotive, ship building, and aerospace industries. But the main problem in aluminium alloy is less endurance to high temperatures and less wear resistance characteristics. In order to overcome these problems, researchers have been reinforcing ceramic particles with AA. In this study SiC and Graphite (Gr) with aerospace grade aluminium alloys and its recent development clearly reviewed. The effects of SiC and Gr on the microstructures, mechanical and wear properties of the composites were studied. From the literature, hardness and tensile strength of the composite increases with increasing SiC content and decreases with increasing graphite. The damping capacity of MMCs dependent on graphite volume fraction and relatively independent on SiC particulates volume fraction. The wear resistance increases with addition of SiC and Gr when compared to the base alloy.

Effect of milling parameters on processing, microstructure and properties of Cu–Al–Ni–Ti shape memory alloys

The effect of milling parameters, such as ball/powder ratio (BPR), milling speed and time, on the microstructural and phase development of powder metallurgy processed Cu–Al–Ni–Ti shape memory alloys has been studied. It has been found that milling for 40 h at a BPR of 40:1, 200 rev min-1 is the optimised condition for mechanical alloying in an attritor mill in order to get a uniform distribution of the alloying elements. A lower BPR caused insufficient milling, whereas a higher BPR led to oxidation of the powder. The complete formation of martensite occurred in the sample prepared under the optimised milling condition followed by cold compaction, sintering at 900°C for 1 h in vacuum and finally quenching. The austenite transformation temperature of the prepared shape memory alloy was found to be ∼208°C. Thus, the developed process enables to curtail the long milling time as well as decrease the prolonged homogenisation treatments.

Processing of Titanium and its Alloys by Microwave Energy

Microwave sintering of titanium and its alloys is a recent development in powder metallurgy of titanium. The sintering in an atmospheric pressure argon gas environment or vacuum is potentially cost effective and energy efficient compared to conventional sintering methods due to the possibility of direct microwave heating of the titanium powder via in-depth energy deposition augmented by hybrid heating in a ceramic casket. The in-depth heating permits very rapid processing (cycle times of potentially less than 10 minutes) which is intended to preserve a very fine grain structure in the final product resulting in excellent mechanical properties and the possibility of superplastic forming. We are investigating this approach using an S–Band microwave system. The process can be also used for composites, laminates, direct alloying, and functionally gradient materials. Evaluations to optimize different parameters for controlling the final density, microstructure, and properties of these materials are underway and results are discussed.

The Contribution of the Bardin Central Research Institute of Ferrous Metallurgy to the Development of Powder Metallurgy in Russia

Scientific research that has been carried out since the middle of the last century at TsNIIchermet has contributed to the progress which has been made in the industrial production of powders of electrolytic iron, titanium, chromium, and stainless steels. The Sulinski Metallurgical Plant began the production of world-class reduced iron powders at the beginning of the 1980s. In the area of refractory materials, a technology was invented to make large powder semifinished products of Mo and W and use them to produce wrought heat-resistant and heavy alloys. In the 1970s, the Institute began work on the production of a new class of powder materials based on intermetallides of the system Ni–Al and alloys of the system Fe–Cr–Al. These materials are now being used in rocketry and aviation thanks to their exceptional resistance to creep, scaling, and heat.

60 years of powder metallurgy at the I. P. Bardin Central Research Institute of Ferrous Metallurgy

This article is devoted to the history of the development of powder metallurgy at the Central Research Institute of Ferrous Metallurgy over a 60-year period. It also looks at the history of the Powder Metallurgy Laboratory, which was established in 1946. Information is presented on technologies that have been developed to obtain iron and alloy powders, and their uses are discussed along with the methods employed to make semifinished products and parts composed of powder metals and alloys.

Main stages of development of powder metallurgy at the central scientific research institute of ferrous metallurgy

Main stages of development of powder metallurgy at the central scientific research institute of ferrous metallurgy

Intensity and Toughness Parameters of Porous Materials

It is of practical importance to establish the relationship between intensity andtoughness parameters and porosity of porous materials. This is of benefit not onlyto the development of powder metallurgy but to the damage mechanics theoryas well. Porous materials can be separated into two types according to the properties ofvoids distribution, i.e. the simple porous materials and the complicated porous materi-als. The voids for the former are completely random in shape, size, and distribution,and therefore, these porous materials are homogenous and isotropic in macroscopicscale from the statistical viewpoint. Conversely, the voids for the latter are not ran-

Developments of the Belarussian Republic scientific and production union for powder metallurgy in the area of new materials and methods and their use in machine building

Today the Republic of Belarus is emerging as a region of skilled machine building, of developed chemical, petrochemical, light, and food industries, and electronics. Traditional products of the specialization of its industry are wheeled tractors, trucks, metal cutting tools, automatic lines, wrist-watches, motorcycles, television sets, computers, household refrigerators, bicycles, bearings, and electrical equipment. This determines the directions of scientific investigations in the area of powder metallurgy including the development of new materials and effective methods of production from them of parts of mechanisms, machines, equipment, etc. The start of development of powder metallurgy in the republic was the creation in 1957 of a special laboratory in the Department of Metals Technology of the Belorussian Polytechnic Institute. In 1980 there was formed the Belorussian Republic Scientific and Production Union for Powder Metallurgy, which included the Scientific-Research and Design Technology Institute for Powder Metallurgy (the head organization) and Molodechno Powder Metallurgy Plant. The path of development of power metallurgy in the republic was long and complex. For example, while in 1960 there were two areas in Belorussia with a total volume of production of about 20 tons of parts, in 1990 14 areas, shops, and a plant with a total volume of production of 8500 tons had been placed in service. In the territory of the republic alone more than 50 areas for the application of coatings have been created in recent years with the direct participation of the union. Today the primary directions in the activity of the union are development of the theoretical fundamentals of use of pulsed loads for creation of powder and composite materials with increase physicomechanical and functional properties, the development of new powder and composite materials and progressive methods of production from them of parts for machine building and other branches of technology with use of methods of static pressing, hot and cold forming, and sintering of freely poured powder, development of the theoretical fundamentals of application of protective coatings on machine and tool parts, and the development of equipment for accomplishment of them. As the result of training of engineering and scientific personnel in the Belorussian Polytechnic Institute (now the Polytechnic Academy) a well operating chain of scientific research-design and technology development-experimental production-industrial production-training of personnel has been established. In the union a broad range of materials which have found use in the machine building, radio and electronics, and electrical industries has been developed. To satisfy the requirements of industry Molodechno Powder Metallurgy Plant has started production of new forms of highly effective production such as blanks for electrical machinery commutators, gear hydraulic pump parts, friction parts, thermal tubes, and filters. New tribotechnical and constructional materials, coatings resistant to wear and corrosion, and porous materials are being developed. High-Density Constructional Materials and Parts of Powder Metallurgy Ferrous and Nonferrous Metals Produced with Use of Plastic Deformation of the Sintered Blanks. One of the effective methods of increasing the physicomechanical properties of ferrous and nonferrous metal-base powder metallurgy materials is plastic deformation of sintered powder metallurgy blanks in the cold condition and with heating. The essence of these processes is plastic flow of the sintered material under the action on it of external loads at normal or increased temperatures. This provides production of parts of the required

Mechanical and metallurgical properties of P/M porous materials

The Development of powder metallurgy in the manufacturing of industrial products necessitates more investigation into pre processes and also into the behavior of P/ M parts. Porous metallic materials are produced only by powder metallurgy methods, due to the nature of the method and its ability in controlling the amount, size and distribution of porosity. Among porous metallic materials, bronze P/ M parts have interest and industrial applications. In this project, the mechanical and metallurgical behavior of sintered porous bronze powder has been studied.

Review of: “ MODERN DEVELOPMENTS IN POWDER METALLURGY: VOLUME 21” Compiled by P. Ulf Gummeson and D.A. Gustafson Metals Powder Industries Federation American Powder Metallurgy Institute 105, College Road East, Princeton, New Jersey 08540 781 pages, hardbound, 1988.

Review of: “ MODERN DEVELOPMENTS IN POWDER METALLURGY: VOLUME 21” Compiled by P. Ulf Gummeson and D.A. Gustafson Metals Powder Industries Federation American Powder Metallurgy Institute 105, College Road East, Princeton, New Jersey 08540 781 pages, hardbound, 1988.

A review of: “MODERN DEVELOPMENTS IN POWDER METALLURGY Volume 19” edited by P.U. Gummeson and D.A. Gustafson Metal Powder Industries Federation American Powder Metallurgy Institute 105 College Road East, Princeton, New Jersey 08540 785 pages, hardcover, 1988.

A review of: “<i>MODERN DEVELOPMENTS IN POWDER METALLURGY Volume 19</i>” edited by P.U. Gummeson and D.A. Gustafson Metal Powder Industries Federation American Powder Metallurgy Institute 105 College Road East, Princeton, New Jersey 08540 785 pages, hardcover, 1988.

A review of: “MODERN DEVELOPMENTS IN POWDER METALLURGY Volume 20”

(1991). A review of: “MODERN DEVELOPMENTS IN POWDER METALLURGY Volume 20”. Materials and Manufacturing Processes: Vol. 6, No. 2, pp. 361-364.

A review of: “REVIEW OF MODERN DEVELOPMENTS IN POWDER METALLURGY” compiled by P.U. Gummeson and D. Gustafson Metal Powder Industries Federation American Powder Metallurgy Institute 105 College Road East, Princeton, NJ 08540 838 pages, hardcover, 1988.

(1990). A review of: “REVIEW OF MODERN DEVELOPMENTS IN POWDER METALLURGY” compiled by P.U. Gummeson and D. Gustafson Metal Powder Industries Federation American Powder Metallurgy Institute 105 College Road East, Princeton, NJ 08540 838 pages, hardcover, 1988. Materials and Manufacturing Processes: Vol. 5, No. 4, pp. 673-676.

The most important tendencies in the development of powder metallurgy. II. Progress in the area of development of new materials (review)

The most important tendencies in the development of powder metallurgy. II. Progress in the area of development of new materials (review)

Developments in powder metallurgy (PM) materials

Some of the developments in PM materials presented at the International Conference, ‘PM 88’, held in Orlando, Florida in June 1988 are discussed. Particular attention is given to the use of PM parts in automotive engineering, metal cutting applications and soft magnetic materials produced by metal injection moulding (MIM). The winning entries in the 1988 PM Part of the Year competition are described.