High-manganese nitrogen-free high-strength and high-toughness anti-hydrogen embrittlement austenitic stainless steel and preparation method thereof

Abstract

The invention discloses a high-manganese nitrogen-free high-strength and high-toughness anti-hydrogen embrittlement austenitic stainless steel and a preparation method thereof. The austenitic stainless steel comprises the following chemical components of less than 0.05% of C, less than 0.50% of Si, 6%-10% of Mn, 12%-16% of Cr, 4.5%-6.5% of Ni, 0.5% -3% of Mo, less than 0.01% of S, less than 0.03%of P, and the balance Fe and trace added Nb, Ti, V, Al, Cu and inevitable impurity elements. The manufacturing method comprises the steps of smelting (casting), forging (hot rolling), rolling, tempering and the like. The high-strength and high-toughness stainless steel prepared by the preparation method disclosed by the invention is characterized in that the high-strength and high-toughness stainless steel is based on 13Cr-5Ni-2Mo / 15Cr-6Ni-2Mo super martensite stainless steel, the austenitic stainless steel is subjected to austenitizing by adding cheap Mn elements, the high strength is achieved through the residual martensite back stress strengthening and the fine crystal strengthening of an austenite matrix, the high toughness is obtained through phase change, and the H2S (hydrogen embrittlement) stress corrosion resistance of the material is improved through the austenitizing. The prepared high-strength steel has extremely high toughness and anti-hydrogen embrittlement performancewhile maintaining good corrosion resistance. The method disclosed by the invention is simple in process, easy to realize industrialization, and capable of being used for an oil pipe containing H2S oil(gas) and an environment with high corrosion resistance and anti-hydrogen embrittlement requirements.

Description

technical field [0001] The invention relates to a high-strength, high-toughness and anti-hydrogen embrittlement austenitic stainless steel with high manganese, low carbon and no nitrogen and a preparation method thereof, in particular to a high-strength stainless steel that can be used as deep well oil and gas pipeline materials and crude oil and natural gas transportation equipment materials. Background technique [0002] The 13Cr / 15Cr stainless steel commonly used in my country is mainly martensitic stainless steel, and the main alloying elements are C and Cr. This type of steel is widely used because of its high hardness and low cost. Unfortunately, due to the addition of a large amount of C, Cr 23 C 6 , to reduce the effective Cr content, while the generated Cr 23 C 6 It is easy to segregate at the grain boundary and cause intergranular corrosion. Therefore, the corrosion resistance of traditional martensitic stainless steel is facing serious challenges in the harsh...

AI Technical Summary

Problems solved by technology

[0005] For the above-mentioned modified 13Cr / 15Cr type super martensitic stainless steel, it is restricted by its martensite matrix, which usually leads to its low toughness. 2 S is very sensitive to stress corrosion

Images