Economic duplex stainless steel with excellent cold forging performance and manufacturing method thereof

Abstract

The invention discloses economic duplex stainless steel with excellent cold forging performance and a manufacturing method thereof. The economic duplex stainless steel comprises the following chemical composition in percentage by weight: 0.01 to 0.07 percent of C, 0.1 to 1.0 percent of Si, 4.0 to 7.0 percent of Mn, 21.5 to 23.5 percent of Cr, 1.8 to 3.5 percent of Ni, 0.08 to 0.15 percent of N, 0 to 0.5 percent of Mo, 0.1 to 1.5 percent of Cu and the balance of Fe and inevitable impurities. The Ni is replaced by a proper amount of Mn and N, in order to guarantee the corrosion resistance of the alloy, the Cr content is controlled to 21.5 to 23.5 percent, and 0 to 0.5 percent of Mo is added; in order to reduce the yield strength and work-hardening rate of materials and improve the cold forging performance of the materials, the N content is controlled between 0.08 and 0.15 percent, and 0.1 to 1.5 percent of Cu is added. The economic duplex stainless steel has excellent corrosion resistance and excellent cold forging performance and can be applied to stainless steel fasteners, silk screen and other industries in a large scale under the condition that the content of the Ni, Mo and other precious metals is low, and 304-austenitic stainless steel with high cost is partially substituted.

Description

technical field [0001] The invention relates to the field of metallurgy, in particular to an economical duplex stainless steel with excellent cold heading performance and a manufacturing method thereof. Background technique [0002] Duplex stainless steel is composed of ferrite and austenite dual phases at room temperature, and the proportion of any phase is not less than 40%. Therefore, duplex stainless steel has the advantages of both ferritic stainless steel and austenitic stainless steel. Compared with austenitic stainless steel, the strength of duplex stainless steel, especially the yield strength, is significantly improved, which is about twice that of austenitic stainless steel; intergranular corrosion resistance, stress corrosion resistance, corrosion fatigue resistance and wear resistance are significantly improved. Compared with ferritic stainless steel, it has high toughness, low brittle transition temperature, intergranular corrosion resistance and significantly ...

AI Technical Summary

Problems solved by technology

For materials that require cold heading, low strength and weak work hardening are required, and the current economical duplex stainless steel system usually contains higher N content and lower Cu content in order to pursue economy and weldability. Suitable for cold heading

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