High-strength welded steel pipe for airbag inflator and method for manufacturing the same

摘要: Disclosed is a high-strength welded steel pipe for airbag inflators that has high toughness and workability. A base material portion of the composition containing, in mass %, C: 0.02 to 0.08%, Si: 0.001 1.0%, Mn: 0.1 2.0%, P: 0.1% or less, Al: 0.01 0.1%, N: 0.01% Ti: 0.20%, V: 0.50%, with balance being Fe incidental impurities. The structure includes ferrite phase having an average grain size 10 μm less at area fraction 90% more Ti, V-based carbide nm dispersed phase. tensile strength TS 780 MPa strength-elongation TS×El 15,000 % more. difference ΔHV Vickers hardness between 60 points less. In softened different from by least 30 points, width Ws circumferential direction 0.05 mm