The technology of powder production from grinding sludge of high-temperature steel 40Kh10S2M is developed. It is shown that processing the grinding sludge of steel 40Kh10S2M in a ball grinder at 60 to 80°C for one hour with subsequent washing with detergents, magnetic separation, and annealing in a restorable medium produces powder with satisfactory technological characteristics. In this processing, the consumption of detergents is decreased, water can be recycled, and extracted oil is sent for recycling. The powder can be densified by adding a plasticizer (polyvinyl alcohol) and granulating the mixture. The technology permits producing compacts with a density of 5.6 to 5.8 g/cm 3 at pressure of 800 MPa. The powder is recommended as a raw material for powder metallurgy.Producing a metal powder is an initial operation in powder metallurgy. The expediency of a production method depends on the economic evaluation of the entire process. Production of powders from waste [1, 2], that permits higher effectiveness of part production technologies and solution of ecological problems, is becoming more popular. The paper [3] has established that sludge of high-temperature steel 40Kh10S2M resulting from grinding car valves can be processed into a powder suitable for use in powder metallurgy. Sludge processing includes the following operations: washing to remove lubricating coolant and oil, dehydration, drying, magnetic separation, and annealing in producer gas. The powder produced with this technology has the following properties: bulk density in vibration filling of 1.17 g/cm 3 ; zero fluidity in testing according to GOST 20899-75; compactability (according to GOST 25280-82) in vibration filling of the powder into the matrix and pressure of 800 MPa no more than 5.47 to 5.50 g/cm 3 . However, cracks form on compacts at this pressure. Note that unsatisfactory process properties of the powder (zero fluidity, small bulk density, low compactability and formability) almost exclude its use for pressing parts with automatic molds.In addition, vibration filling of the matrix should be used in manual pressing. The technology does not provide for recycling sludge treatment waste, especially water.This study is intended to improve the technology of powder production from sludge of steel 40Kh10S2M to ensure better properties of the powder.Grinding sludge of steel 40Kh10S2M contains 70% of metal fractions, 10% of nonmetal fractions (disintegration products of abrasive tools in grinding), and 20% of lubricating coolant [3]. More than 10 to 15% of the sludge are conglomerates of oxidized metal and nonmetal particles cemented by lubricating coolant. Metallographic analyses have established that the metal part consists of different chips: thin curly; oblong, curved (scimitar-shaped); and in the form of splintered particles (Fig. 1). The mean sizes of the chips are as follows: curly chips have 0.015 to 0.110 mm in thickness and 0.5 to 2.5 mm in length; oblong chips have 0.006 to 0.025 mm in thickness and 0.05 to 0.2 mm in length; splintered p...

A new mathematical simulation technique for physico-mechanical properties of multicomponent powder materials is proposed in this paper. The main advantage of the technique is that finite elements representing different components are placed into a common mesh and may exchange their properties. The input data are properties of components and specified value of porosity. The output data are properties of material after sintering. The technique allows us to investigate the influence of each component of a material on the properties and distribution of properties inside the sample. The comparative analysis of materials with different compositions is based on simulation results that are well concordant with the results of the laboratory experiments.

The paper examines how temperature and strain rate influence the deformation of a porous powder billet made of an antifriction material. Copper and nickel-based alloy powders produced from industrial waste are used as the initial material. The ultimate strain in compression is established and used to calculate the mold sizes in tool development. Ambiguous temperature dependence of the mechanical and antifriction properties is obtained. Temperature and strain rate that ensure satisfactory mechanical and antifriction properties are found. Processes for producing parts from the antifriction material are proposed.Powder antifriction materials have been increasingly used in industry along with compact alloys. The replacement of nonferrous metal compact alloys with copper-based antifriction materials serves two purposes: saves resources and increases the reliability and lifetime of friction units [1,2]. Copper-based powder materials are somewhat inferior to cast ones in their mechanical properties because of pores, but their performance characteristics, especially wear resistance, are much better [3]. Materials based on nonferrous metals are expensive and not readily available and require flood lubrication in operating units.This paper determines the strain rate and temperature for forming porous powder billets made of antifriction material produced from industrial waste.To make antifriction material, copper powder was used. This powder was produced from waste of M1 conductors as follows. The waste was annealed at 800°C in a hydrogen-containing medium, reduced in a knife grinder, and insulation particles were removed by air separation. The fibers 0.5 to 30 mm long were ground into powder in a hammer mill. Iron inclusions were removed by magnetic separation. Reducing annealing of the powder was conducted in generator gas at 550°C for 1 h. After the porous, easily disintegrating sponge was removed, it was repeatedly ground in a hammer mill [4]. The copper powder from waste had the following chemical composition, wt.%: Cu is no more than 99.70; Fe no more than 0.18; O no more than 0.10; Si no more than 0.10; and calcined residue (after treatment of the powder with nitric acid) no more than 0.05.To harden the material, copper powder was mixed with nickel-based alloy powder produced from waste of alkali nickel-cadmium accumulator electrodes using the following process. Positively charged lamels were removed from the accumulators, which had been disassembled by hand, immersed into weak sulfuric acid solution to remove residues of alkali solution, and then washed with water. After that, the lamels were heated to 600°C in a furnace without protective medium, cooled down in water at a rate of 60 °C/sec, and air-dried. Next, the lamels were 1 V. Dal' East

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