High-hardness corrosion-resistant cast stainless steel for fluid transportation

Abstract

The invention discloses high-hardness corrosion-resistant cast stainless steel for fluid transportation. A stainless steel casting comprises the following chemical components in percentage: equal to or less than 0.03% of C, equal to or less than 1% of Si, equal to or less than 2% of Mn, equal to or less than 0.03% of S, equal to or less than 0.04% of P, 25-28% of Cr, 4-6% of Ni, 4-8% of Mo, 0-5% of Cu, 0-0.3% of N and the balance of Fe and unavoidable impurities, wherein the range of Mo / Ni is 0.75-1.5, and PREN=(Cr+3.3*Mo+16*N) is equal to or greater than 41. The manufacturing process flow isas follows: smelting, casting, solid solution and hardening treatment; through ingredient improvement, a texture is obtained, and the content of solid solution state ferrite of the texture is far greater than that of common duplex stainless steel; the phase proportion requirement of the duplex stainless steel is 30%-70%; and the content of ferrite of the high-hardness corrosion-resistant cast stainless steel is equal to or greater than 70%, so that the hardness of the stainless steel is greatly improved; and the corrosion resistance and high hardness performance are further realized through the smelting, casting, solid solution and hardening treatment.

Description

technical field [0001] The invention belongs to the technical field of high-hardness corrosion-resistant stainless steel, in particular to a high-hardness corrosion-resistant cast stainless steel used for fluid transportation. Background technique [0002] Existing stainless steels include austenitic stainless steel, ferritic stainless steel, martensitic stainless steel, duplex stainless steel, precipitation hardening stainless steel, etc. Except for martensitic stainless steel and precipitation hardening stainless steel, which can be strengthened by heat treatment, the rest of the stainless steels are usually in solid solution. It is difficult to meet the requirements of cavitation erosion and abrasive wear during fluid transportation. For example, if the medium temperature precipitation is used for strengthening, the corrosion resistance of the material is seriously affected by the local depletion of elements due to phase precipitation. Since duplex stainless steel is comp...

AI Technical Summary

Problems solved by technology

Caused a huge waste of materials and manpower

[0004] The existing technology usually solves the wear problem by partial surfacing or spraying wear-resistant coatings, but due to the high brittleness, thin thickness, high price, and high requirements on the manufacturing process of the wear-resistant layer, abnormal failures are prone to occur during actual use , leading to downtime and huge losses

Therefore, such solutions are usually not used for important fluid delivery occasions

Images