| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a dissimilar metal joint product between a nickel-titanium alloy material and a pure titanium material, which comprises a joint having a tensile strength which is not less than the tensile strength of the pure titanium material before joining, has no significant variation in strength of the joint, and has no significant heat-affected zone after joining, and a joining method therefor. <P>SOLUTION: A round rod 1 formed of a nickel-titanium alloy material and a round rod 2 formed of a pure titanium material are joined to each other in such a manner that, while rotating at least one of the joining surface of the round rod 1 and the joining surface of the round rod 2 for frictional pressure welding, after the start of deceleration of the rotation, a predetermined upset force is applied in a period where the peripheral velocity in the outermost periphery of the rotation in the joining face is not less than 0.5 m/sec to compress and integrally join the assembly. In the joint, a structure of a reaction layer formed by the compressive force caused by the upset force and the rotatory power of the rotation which deaccelerates, is formed, and the joint has a tensile strength which is not less than the tensile strength of the pure titanium material before joining. <P>COPYRIGHT: (C)2009,JPO&INPIT |
