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AssigneeJfe Steel Corporation
InventorsMasatoshi Aratani, Ryoji Matsui, Tomonori Kondo, Shinsaku Kokubo
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An electric resistance welded steel pipe for manufacturing a hollow stabilizer has a Lankford value in a pipe longitudinal direction of from 0.7 to less than 1.0. The electric resistance welded steel pipe is subjected to cold bending and then to a heat treatment including quenching and tempering to manufacture a stabilizer. The cold bending is cold rotary draw bending. When bent with a bend radius of from 1.0 times to 3.0 times an outer diameter of the pipe before cold bending, a flattening ratio is from 0% to 10%, a thickness reduction rate on a bending outside and a thickness increase rate on a bending inside are from 0% to 10%, and additionally, a circumferential length change of a bending center portion is from 0% to 10%. A Vickers hardness of the stabilizer after the heat treatment is adjusted to from 400 HV to less than 580 HV.
An electric resistance welded steel pipe for manufacturing a hollow stabilizer, having a yield ratio (YS/TS) of 0.7 or more, a uniform elongation U-EL of 10% or more, and a Vickers hardness of from 400 HV to less than 580 HV, wherein a Lankford value (r value) in a pipe longitudinal direction is from 0.7 to less than 1.0.
Dependencies are inferred from the claim text.