Patent ID: 7566416

Claim:
A steel pipe for use in an airbag inflator, which has a steel composition comprising, in mass %, C: 0.05-0.20%, Si: 0.1-1.0%, P: at most 0.025%,S: at most 0.010%, Cr: 0.05-1.45%, Al: at most 0.10%, one or both of Ti and Mn in amounts satisfying the following equations (1) and (2), Ti≦0.02% (1) 0.4% ≦Mn +40Ti ≦1.2% (2) Mo: 0-1.0%, Ni: 0-1.5%, V: 0-0.2%,B: 0-0.005%, Cu: 0-0.5%, Nb: 0-0.1%, Ca: 0-0.01%, Mg: 0-0.01%, REM: 0-0.01%, and a remainder of Fe and impurities, wherein the ratio (referred to below as {110}L/T) of the X-ray integrated intensity ratio for the {110}plane measured in a cross section perpendicular to the axial direction L of the steel pipe to the X-ray integrated intensity ratio for the {110}plane measured in a cross section perpendicular to the circumferential direction T of the steel pipe is at least 13.4 and at most 50, and the steel pipe has a tensile strength of at least 900 MPa and a low temperature toughness corresponding to a value of vTrs100 of −40 degrees C. or below.