| 摘要 |
<p>An electric welded steel tube for a hollow stabilizer, which has a chemical composition, in mass %: C: 0.20 to 0.35 %, Si: 0.10 to 0.50 %, Mn: 0.30 to 1.00 %, Al: 0.01 to 0.10 %, Cr: 0.10 to 1.00 %, Mo: 0.005 to 1.00 %, Ti: 0.001 to 0.02 %, B: 0.0005 to 0.0050 %, N: 0.0010 to 0.0100 % and balance: Fe and inevitable impurities, provided that the formula: N/14 < Ti/47.9 is satisfied, and exhibits an ideal critical diameter (Di) of 1.0 (in) or more, an n value in the tube axis direction of 0.12 or more, a difference in hardness between an electric weld zone and a base material of 30 in terms of Hv, an average ferrite crystal grain diameter of 3 to 40 νm, a percentage of an area occupied by ferrite crystal grains having an aspect ratio of 0.5 to 3.0 relative to the total area of the ferrite phase thereof of 90 % or more, and also has a second phase having an average size of 20 νm or less. The electric welded steel tube for a hollow stabilizer exhibits excellent formability.</p> |
