Ultra-high strength maraging stainless steel with salt-water corrosion resistance

US11085093B2 · kind B2 · utility

Assignees

• The Boeing Company · US
• Institute of Metal Research · CN

Inventors

• Jialong Tian · Shenyang, CN
• Ke Yang · Zhuolan Township, TW
• Wei Wang · Hsinchu, TW
• Yiyin Shan · Shenyang, CN
• Wei Yan · Lo Wu, CN

Key dates

• Filing date: Jul 5, 2017
• Grant date: Aug 10, 2021
• Expiry date: Jul 5, 2037

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C21D2211/008
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

An ultra-high strength maraging stainless steel with nominal composition (in mass) of C≤0.03%, Cr: 13.0-14.0%, Ni: 5.5-7.0%, Co: 5.5-7.5%, Mo: 3.0-5.0%, Ti: 1.9-2.5%, Si: ≤0.1%, Mn: ≤0.1%, P: ≤0.01%, S: ≤0.01%, and Fe: balance. The developed ultra-high strength maraging stainless steel combines ultra-high strength (with σb≥2000 MPa, σ0.2≥1700 MPa, δ≥8% and ψ≥40%), high toughness (KIC≥83 MPa·m½) and superior salt-water corrosion resistance (with pitting potential Epit≥0.15 (vs SCE)). Therefore, this steel is suitable to make structural parts that are used in harsh corrosive environments like marine environment containing chloride ions, etc.