Nitrogen-containing stainless bearing steel and preparation method thereof

Abstract

The invention relates to nitrogenous stainless bearing steel and a preparation method thereof. The bearing steel comprises the following components in percentage by weigh: 0.25-0.45% of C, 14.00-17.00% of Cr, 0.50-3.00% of W, less than or equal to 0.80% of Mo, less than or equal to 3.00% of Ni, less than or equal to 0.50% of Co, less than or equal to 0.20% of Cu, 0.10-0.50% of N, less than or equal to 1.00% of Si, less than or equal to 1.00% of Mn, less than or equal to 0.02% of S, less than or equal to 0.03% of P and the balance of Fe. The preparation method comprises the following steps: a, smelting in vacuum, b, remelting electroslag, c, forging, and d, performing thermal treatment. The bearing steel is nitrogenous martensite stainless bearing steel, is good in corrosion resistance, mechanical property and temperature resistance and high in hardness, and can be applied to corrosive environments such as the astronavigation industry, the ocean industry, the railway industry, the petroleum and chemical industry, the food industry, the paper-making industry and the intelligent industry after being made into shafts and bearings.

Description

technical field [0001] The invention relates to a stainless steel, in particular to a nitrogen-containing martensitic stainless bearing steel and a preparation method thereof. Background technique [0002] Bearings are important parts of various mechanical equipment and play an extremely important role in the national economy and national defense. Bearing materials are the basis of bearings. Bearings have different requirements for bearing materials under different service conditions. For example: under high pressure and impact service conditions, materials are required to have high mechanical properties; wear and fatigue service conditions require materials to be wear-resistant and fatigue-resistant; long life and high reliability require materials to have high uniformity and high processing accuracy; consider the economical characteristics of materials It requires low material cost and strong machinability; in corrosive environments such as aerospace, ocean, wind power, ra...

AI Technical Summary

Problems solved by technology

At present, bearing materials serving in corrosive environments include 1Cr18Ni9Ti (3YC32) and 0Cr17Ni12Mo2 (3YC20) austenitic stainless steels. The hardness of these stainless steels is low, even if they are cold hardened, the hardness is not high, and the production process is difficult; 0Cr17Ni7Al (3YC30), 0Cr17Ni4Cu4Nb (6YC5) precipitation hardening stainless steel, its hardness

The most used are 9Cr18 and 9Cr18Mo (6YC9) martensitic stainless bearing steel and 0Cr40Ni55Al3 (6YC2B) corrosion-resistant bearing alloy with the best comprehensive performance. Although these stainless steels have the characteristics of high hardness (up to HRC55 or more), 9Cr18 and The carbon content of 9Cr18Mo is relatively high, and there are more eutectic carbides in the structure, with coarse particles and uneven distribution, most of which are distributed on the grain boundaries. The eutectic carbides peel off from the processed surface and form pits, which affect the surface quality and processing Accuracy, and in the process of use, stress concentration is formed at the eutectic carbide and fatigue cracks are generated, which affects the service life of the bearing; 0Cr40Ni55Al3 is a high-alloy material, and the iron is only a trace amount, while the chromium and nickel content in the material are high and the price is low. It is expensive, and the material is non-magnetic, and the conventional magnetic clamping process cannot be used in the processing of the bearing ring, and the processing method of magnetic clamping processing must be used for the magnetic material in the sleeve. Therefore, the bearing alloy material and processing costs are very high.

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