Nitriding of niobium steel and product made thereby

US11193188B2 · kind B2 · utility

Assignee

• Nucor Corporation · US

Inventors

• Yuxuan Xie · Clare, AU
• Chen Zhu · Sydney, AU
• Julie M. Cairney · Sydney, AU
• Simon P. Ringer · Sydney, AU
• Christopher Ronald Killmore · Wollongong, AU
• Frank Barbaro · Wollongong, AU
• James Geoffrey Williams · High Point, US

Key dates

• Filing date: Nov 28, 2018
• Grant date: Dec 7, 2021
• Expiry date: May 3, 2039

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C23C8/50
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A nitrided steel product or thin cast steel strip comprising, by weight, less than 0.25% carbon, between 0.20 and 2.0% manganese, between 0.05 and 0.50% silicon, less than 0.01% aluminum, niobium between 0.01 and about 0.20%, and between 0.01 and 0.075% nitrogen, and having a majority of the microstructure comprised of bainite and acicular ferrite, having more than 70% niobium in solid solution prior to nitriding and having yield strength between 650 MPa and 800 MPa and tensile strength between 750 MPa and 900 MPa.