ESTIMATION METHOD OF NUGGET DIAMETER OF RESISTANCE SPOT WELDING

摘要

PROBLEM TO BE SOLVED: To provide an estimation method of a nugget diameter of resistance spot welding capable of predicting a weld lobe under a condition of requiring consideration of a distributary of an electric current, on a desk, by using the weld lobe of already acquired single point welding.SOLUTION: In an estimation method of a nugget diameter of resistance spot welding, kof I=k×Iis determined by using a thickness (t) of a welding object material, an electric current Iflowing between electrodes for sandwiching the welding object material, an electric current Iflowing in a welding point, a distance (b) between the welding point and an already dotted point, a nugget diameter dof the welding point in the case of single point welding, a nugget diameter dof the welding point and the already dotted point when welded under the same welding condition as the single point welding, specific resistance of a welding part and specific resistance of a distributary part, and the determined kis substituted in a relational expression of dand d, and the nugget diameter in the already-known weld lobe of the single point welding is substituted in dof the relational expression, so that the nugget diameter is estimated when having the already dotted point corresponding to a current condition.