Search Results for copper alloy powder

This article describes the fundamentals of various techniques used for the production of copper and copper alloy powders. These include atomization (water, air, and gas), oxide reduction, and electrolysis. The article discusses the effects of electrolyte composition and operating conditions on the characteristics of copper and copper alloy powders.

Selection of the process steps used, powder chosen, and lubricant choice have marked effects on the quality of a sintered component. This article describes the alloy composition, mechanical and structural properties, processing routes, and advantages of the common members of the copper alloy family, namely, pure copper, brass, and bronze, which all aid in the selection of the suitable material for structural and bearing applications. It outlines the structural applications of nickel silver alloys.

This article discusses the characteristics, properties, and production methods of copper powders and copper alloy powders. Bulk of the discussion is devoted to production and applications of powder metallurgy (P/M) parts, including pure copper P/M parts, bronze P/M parts, brass and nickel silver P/M parts, copper-nickel P/M parts, copper-lead P/M parts, copper-base P/M friction materials, copper-base P/M electrical contact materials, copper-base P/M brush materials, infiltrated parts, and oxide-dispersion-strengthened copper P/M materials.

This article briefly reviews the subject of copper-base powder-metallurgy (P/M) products in terms of powder production methods (atomization, oxide reduction, electrolysis, and hydrometallurgy) and the product properties/consolidation practices of the major applications. Of the four major methods for making copper and copper alloy powders, atomization and oxide reduction are presently practiced on a large scale in North America. The article provides information on the mechanism, production, properties, composition and applications of different types of copper-base P/M products, including self-lubricating sintered bearings, structural parts, oxide-dispersion-strengthened copper, sintered metal friction materials, and porous filters.

Bronze and brass alloys are two key classes of materials in copper-base powder metallurgy applications. They are often compacted using mechanical or hydraulic pressing machines. This article provides an overview of the powder pressing process, providing information on the powder properties of bronze and brass and the roles of lubricant and compaction dies in the pressing process. It discusses the structural defects that originate during the compaction process. The article also describes the major factors that influence the sintering response in bronze, prealloyed bronze, brass, and nickel-silver.

This article is a detailed account of additive manufacturing (AM) processes for copper and copper alloys such as copper-chromium alloys, GRCop, oxide-dispersion-strengthened copper, copper-nickel alloys, copper-tin alloys, copper-zinc alloys, and copper-base shape memory alloys. The AM processes include binder jetting, ultrasonic additive manufacturing, directed-energy deposition, laser powder-bed fusion, and electron beam powder-bed fusion. The article presents a review of the literature and state of the art for copper alloy AM and features data on AM processes and industrial practices, copper alloys used, selected applications, material properties, and where applicable, compares these data and properties to traditionally processed materials. The data presented and the surrounding discussion focus on bulk metallurgical processing of copper components. The discussion covers the composition and performance criteria for copper alloys that have been reported for AM and discusses key differences in process-structure-property relationships compared to conventionally processed material. The article also provides information on feedstock considerations for copper powder handling.

Metal powders are used as fuels in solid propellants, fillers in various materials, such as polymers or other binder systems, and for material substitution. They are also used in food enrichment, environmental remediation market, and magnetic, electrical, and medical application areas. This article reviews some of the diverse and emerging applications of ferrous and nonferrous powders. It also discusses the functions of copier powders and the processes used frequently for copier powder coating.

This article provides information on the most frequently used atmospheres in commercial sintering of powder metallurgy iron and steel materials. These include endothermic, exothermic, dissociated ammonia, pure hydrogen, and nitrogen-base atmospheres. The article discusses sintering of iron and iron-graphite powder, iron-copper and iron-copper graphite, and alloy steels. The effects of various sinter conditions on the amount of combined carbon formed in the steel are also discussed. The article concludes with information on high-temperature sintering and sinter hardening.

This article provides information on the microstructure of powder metal alloys and the special handling requirements of porous materials. It covers selection, sectioning, mounting, grinding, and polishing, and describes procedures, such as washing, liquid removal, and impregnation, meant to preserve pore structures and keep them open for analysis. The article compares and contrasts the microstructures of nearly 50 powder metal alloys, using them to illustrate the effect of consolidation and compaction methods as well as particle size, composition, and shape. It discusses imaging equipment and techniques and provides data on etchants and etching procedures.

The two most important classes of materials that are manufactured via infiltration methods are copper- and silver-infiltrated refractory metals and refractory carbides, and copper-infiltrated steels. This article focuses on copper-infiltrated steels and discusses the basic requirements for infiltration, which is a technique that is only applicable to material systems that meet certain requirements. It addresses these requirements and describes the conventional (partial) infiltration process of powder metallurgy (PM) steel. The materials used in the process, such as matrix and infiltrant, are discussed. The article also details several criteria used to evaluate the performance of an infiltration process. It concludes with information on alloy steels and fully infiltrated steels.

This article describes the various specimen preparation procedures for lead, lead alloys, and sleeve bearings, including sectioning, mounting, grinding, polishing, and etching. The microscopic examination and microstructures of lead and lead alloys are discussed. The article also provides information on the microstructures of sleeve bearing materials.

This article focuses on the fractography features of the conventional powdered metal (PM) process for ferrous powders. It discusses porosity, which is one of the inherent features present in components produced by conventional press-and-sinter processes, and green cracks, which are the most common fracture issue in conventional PM processes. It explains the effect of post-sintering operations. The article also presents the common ferrous powder metallurgy materials.

This article focuses on the various criteria considered in the selection of product forms, joint types, solders, and filler metals for brazing and soldering of base material components.

A sliding bearing (plain bearing) is a machine element designed to transmit loads or reaction forces to a shaft that rotates relative to the bearing. This article discusses the properties of bearing materials. It provides information on bearing material systems: single-metal systems, bimetal systems, and trimetal systems. The article describes the designations, nominal compositions, mechanical properties, and applications of various sliding bearing alloys: tin-base alloys, lead-base alloys, copper-base alloys, aluminum-base alloys, silver-base alloys, zinc-base alloys, additional metallic materials, nonmetallic materials. It describes casting processes, powder metallurgy processes, and electroplating processes. The article also discusses the selection criteria for bearing materials.

This article summarizes the general classification, mechanical properties, and applications of ferrous powder metallurgy (PM) materials for parts production. It discusses four principal ferrous PM alloy types: admixed elemental alloys, diffusion alloys, prealloys, and hybrid alloys. The article reviews the benefits and disadvantages as well as the effect of processing on the properties and material microstructure of these alloys. It contains tables that list the mechanical properties of various iron-copper and copper steels.

This article provides a discussion on the process descriptions, processing conditions, and processing variables of the most common chemical methods for metal powder production. These methods include oxide reduction, precipitation from solution, and thermal decomposition. Methods such as precipitation from salt solution and gas, chemical embrittlement, hydride decomposition, and thermite reactions are also discussed. The article also discusses the methods used to produce powders electrolytically and the types of metal powders produced. The physical and chemical characteristics of these powders are also reviewed.

This article briefly reviews the production methods and characteristics of plain carbon and low-alloy water-atomized iron and steel powders, high-porosity iron powder, carbonyl iron powder, and electrolytic iron powder. It emphasizes on atomized powders, because they are the most widely used materials for ferrous powder metallurgy. The article provides information on the properties and applications of these powders. It also includes an overview of diffusion alloying, basics of admixing, and bonded premixes.