SU1044657A1 - Antifriction material based on iron oxide - Google Patents

Description

4 About SP

sj The invention relates to powder metallurgy, in particular to iron-based anti-friction materials, which are used for high-temperature dry-friction units operating in a wide range of ambient temperatures and humidity. Known antifriction material based on iron, containing 0,520% copper 1 1. The disadvantage of this material is its low wear resistance. The closest to the proposed technical essence and the achieved result is an iron-based anti-friction material C2, having the following composition, weight Copper 13-15 Manganese ultraphosphates 0.05-1.5 Iron Other However, the known material has insufficient wear resistance during operation and storage in the atmosphere Fera with normal and especially high humidity. In addition, manganese ultraphosphates, which are part of a known material, have low hydrolytic resistance, as a result of which during operation and storage with normal and especially high humidity quickly decompose with the formation of phosphoric acid, accelerating the corrosion of the iron frame material which entails a decrease its wear resistance. For example, the wear rate of a known material containing 0.5 wt.% Of manganese ultraphosphates when dry rubbed together with steel at a slip speed of k / m and a load of 5 kgf / cm after storage for a year under normal conditions. at 100 C 9, at, at 600 ° C, 8 µm / km, while immediately after sample preparation, the material is worn at 100 C 2, 600 ° C, 1.5 µm / km. 1, with Thus, the wear rate of a known material after storage for a year under normal conditions increases by a factor of -5. The purpose of the invention is to increase the wear resistance when operating in a humid environment in the temperature range 100600 ° C. This is achieved by the fact that an iron-based antifriction material containing copper and a phosphate additive, as a phosphate additive, contains aluminum chromophosphates or chromophosphates in the following ratio of components, Copper13-15 Alumochromophosphates or 0.05-2.0 chromophosphates Remaining Iron Introduced into the proposed material alumochromophosphates (AHFS) or chromophosphates (HFS) dehydrogenate when heated. When the binder solidifies on the surface of the grains, waterproof glassy phosphate films are formed, protecting the metal from oxidation and increasing the strength of the intergranular bond in the material, resulting in increased durability of the material. With the introduction of the sintered frame AHFS or HFS in the amount of less than 0.5 weight. the films are not sufficiently dense, and when the content of AHFS or HFS is more than 2 weight. The binder may cause enhanced corrosion of the surface layer, which also adversely affects the wear resistance of the material. The copper content in the material before impregnation with phosphates should be within the established limits (13 15 weights.), As with a content of 12 wt. copper and less is obtained. a material with high strength (20-25 and correspondingly low mechanical properties, and with a content of 16 weights, copper and more in the sintered material, the pores are closed and not enough to introduce the required amount and ensure uniform distribution of phosphates across the sample section. Pryme R. Iron powders of the brand: ПЖ2МЗ (GOST) and copper of the ПМС-2 brand (GOST 2 БО-78) are mixed in the required proportion, compacted by rolling or pressing and sintered in a medium of dried hydrogen for 1.5 4 i at 1150 C. Sintered porous billets put t into the autoclave. Air is pumped out from the autoclave to a residual pressure of mm Hg, then an aqueous solution of AHFS (TU 6-18-166-73) or HFS of the required concentration is fed to the autoclave. Impregnation of the samples with a saturated aqueous solution of AHFS (density 1, 82 g / cm provides the content of aluminum chlorine phosphates in the material by 2 wt.%. Dilution of the saturated solution with water is 2,; 5; 10; 100 and 1000 times reduce the content of aluminum chromophosphates or chrophosphates in the material, respectively, to 1, it; 0.7; 0, it; 0.15 and 0.05 weight. The exposure time under the solution layer is 15-30 minutes, depending on the size of the blanks. The impregnated samples are subjected to heat treatment in a muffle furnace in coking charge or in an inert gas atmosphere to ensure water resistance, with a gradual increase in temperature from 20 to О OO С at a rate of 25 sec / c. Such heat treatment stabilizes the properties of the impregnated sintered material, resulting in a material containing iron. Copper and chromophosphates or chromophosphates. The table presents the results of tests of the material of the proposed composition in comparison with the known. The antifriction properties of the material are determined by dry friction together with steel at a sliding speed of 4 m / s and a load of 5 kgf / cm after storage of samples for a year at an ambient humidity of 60-90%.

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The table shows that using a wet environment allows you to create

tivanie material proposed friction knots working without lubrication

It helps to increase the wear resistance of co-at elevated temperatures and wetted parts more than in the ambiguity of the environment, to increase their

Thus, a higher durability .5 durability and expand the range

the resistance of the proposed material application.

Claims (1)

IRON-BASED ANTIFRICTION MATERIAL, containing copper and a phosphate additive, characterized in that, in order to increase wear resistance when working in a humid environment in the temperature range 100-600 ^ C, it contains aluminum chromophosphates or chromophosphates as the phosphate additive in the following the ratio of components, wt.%: Copper 13-15 D Alumochromophosphates .or chromophosphates 0.05-2.0 Iron Else SU ,,, 1044657> 1044657 2