| 摘要 |
PROBLEM TO BE SOLVED: To provide a lap resistance spot welding method capable of obtaining requested penetration even on a thinner steel sheet side and free from occurrence of scattering even under the constant pressure during the welding and capable of preventing consumption of an electrode when performing the lap resistance spot welding of three or more steel sheets. SOLUTION: Lapped steel sheets are assembled so that a thinnest steel sheet 3 is brought into contact with a positive side electrode 6, and an insert electrode with a chip consisting of W, Mo or an alloy thereof being embedded is used for the positive side electrode 6 for performing the welding. In this condition, the contact area (S<SP>+</SP>) of the positive side electrode 6 with the steel sheet 3 is preferably determined so as to satisfy≥1/2 and≤3/4 of the contact area (S<SP>-</SP>) of a negative side electrode 5 with a steel sheet 1. COPYRIGHT: (C)2008,JPO&INPIT |
