High-strength stainless steel, heat treatment process and forming member

Abstract

The invention relates to high-strength stainless steel, a heat treatment process and a forming member. The high-strength stainless steel is prepared from the following components according to weight percent: 0.2 to 0.35% of C, 0.7 to 3.50% of Mn, 0.6 to 2.0% of Si, 11 to 17% of Cr, less than or equal to 0.20% of Nb, less than or equal to 0.20% of Ti and the balance of Fe and impurities. The heat treatment process comprises the following steps of (a) heating the high-strength stainless steel to 1000 to 1200 DEG C, and then insulating for 1 to 3600 s; (b) cooling the high-strength stainless steel treated in the step (a) below 100 DEG C; and (c) heating the high-strength stainless steel treated in the step (b) to 150 to 400 DEG C, then insulating for 10 to 10000 s, and then cooling to room temperature in any cooling mode. The forming member is made of the high-strength stainless steel, and the microstructure of the forming member is composed of 5% to 30% of retained austenite, 70% to 95%of martensite, less than 1% of Nb and Ti carbide and less than 2% of Cr carbide in an area.

Description

technical field [0001] The invention relates to a high-strength stainless steel, a heat treatment process and a formed component. Background technique [0002] Commonly used martensitic chromium stainless steels (Cr13, Cr13Mo, etc.) are widely used in knives, steam turbine blades, bearings, valves, structural parts and wear-resistant parts because of their good corrosion resistance and high strength. The hardness of this type of stainless steel is still high after quenching and tempering treatment, and the toughness is improved. With the increase of carbon content, the hardness gradually increases, but the toughness and corrosion resistance gradually decrease. [0003] The most commonly used and cheapest way for high-strength stainless steel is to increase the carbon content in the composition to significantly increase the hardness, but at the same time the toughness is also sharply reduced, and it is difficult to completely dissolve chromium carbides during high-temperature...

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Problems solved by technology

[0006] However, this paper only applied the Q&P process to 3Cr13 steel tentatively, and did not realize the problem of corrosion resistance decline caused by a large number of unsolubilized chromium carbides during high-temperature solution treatment and the stability of its performance. Temperature has a great impact on performance, and the process window is narrow, making it difficult for industrial applications

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