TH2001007444A - Resistance spot welding method and method of fabricating components through welding. - Google Patents

Abstract

The method of resistance spot welding includes: conducting test welding; and the actual welding after the test welding, where the subsequent current passing in the test welding, the passing current is achieved by controlling the constant current under the condition: 0.5 less than or equal to Vtp/Vtm less than or equal to 2.0 when tc is less than or equal to 800 ms; 0.5 - 0.3 x (tc - 800) / 800 less than or equal to Vtp / Vtm less than or equal to 2.0 - 0.5 x (tc - 800)/800 when 800 ms less than or equal to tc < 1600 ms; and 0.2 less than or equal to Vtp /Vtm less than or equal to 1.5 when tc is greater than or equal to 1600 ms, where Vtm is the average of the inter-electrode voltages in the primary passing current in the test welding, and Vtp is the average. of the voltage between the electrodes in the subsequent passing current in the test welding, and where in the primary passing current in the actual welding, adjustable control welding is performed, and in the subsequent passing current in the welding. True, the passing current is carried out with constant current control under the condition: 0.8 x Itp less than or equal to Imp less than or equal to 1.2 x Itp, where Itp is the current in the subsequent passing current in the test connection, and Imp is the current. in the passage of the latter current in the actual welding

Claims (4)

1. Resistance spot welding method which is compression parts to be welded which are sheets A certain amount of metal is overlaid by a pair of electrodes, and the passage of current while applying a force electrodes to connect the parts to be welded The method of resistance spot welding which includes: conducting test welding; and the actual welding after the test weld, where (a) in the test weld, the primary pass is made for nugget formation and passing. Secondary current for subsequent heat treatment To pass the mainstream welding test Momentary quantity time variation curve of heat generated per unit volume and cumulative amount of heat generated per unit The volume was calculated from the electrical properties between the electrodes in the proper nugget formation. By conducting the current passage by the control actuator is stored, and in the subsequent current passage in the test weld, the current passage is performed by Controls exhibited under conditions 0.5 less than or equal to Vtp/Vtm less than or equal to 2.0 when tc < 800 ms; 0.5 - 0.3 x (tc - 800) / 800 less than or equal to Vtp / Vtm less than or equal to 2.0 - 0.5 x (tc - 800)/800 when 800 ms less than or equal to tc < 1600 ms; and 0.2 less than or equal to Vtp/Vtm, less than or equal to 1.5 when tc is greater than or equal to 1600 ms, where Vtm is the average voltage between the electrodes in the primary passage of the test welding current, Vtp is the average force. pressure between electrodes in the secondary current passage in the test welding, and tc is the cooling time between primary and secondary current passage. in test welding, and (b) thereafter in actual welding going through the mainstream for creating nuggets and Post-current pass for subsequent heat treatment, in primary pass in actual welding, time-variation curve of the instantaneous quantity of heat generation per unit volume and cumulative amount of heat generation per unit volume which is stored in the primary passing current in the test welding is set as the target, and adjustable welding controls are made to control the amount of passing current according to the target, and in the secondary passing current. In actual welding, the passage of current is done by a control. Steady current under conditions: 0.8 x Itp less than or equal to Imp less than or equal to 1.2 x Itp, where Itp is the post-pass current in the test welding, and Imp is the post-pass current in the welding process. TRUE 2. Method of resistance spot welding according to claim 1, where in adaptive control welding It has to pass through the real welding mainstream. In the case of the quantity of the time variation of the quantity The moment of heat generated per unit volume differs from the time-variation curve of the volume. The moment of heat generated per unit volume is set as the target. Amount of passing current is controlled in order to compensate for the difference from the time variation curve within the welding time. residual in passing the main current in the actual welding so that the accumulated amount of heat generated The unit of passage volume of the main current in actual welding corresponds to the accumulated heat. generated per unit volume set as a target 3. Resistance spot welding method according to Claim 1 or 2, where the cooling time is obtained. Determination between primary and secondary passage in actual welding, and number of welding interval repetitions for cooling time and secondary passage. After passing two or more times the actual welding mainstream 4. Method for manufacturing welded components that include Joining a number of overlapped metal sheets by means of spot resistance welding, according to any one of clauses 1 to 3.