Welding equipment for metallic materials and method for welding metallic materials

10:

• A method for spot-welding metallic materials by sandwiching the metallic materials with a pair of electrodes and energizing the metallic materials, comprising:
• a first step for heating and spot-welding a given region of the metallic materials by a first energization applying electric power having a low frequency or DC to the pair of electrodes;
• and
• a second step for heating a region different from the region in the first step by a second energization applying electric power having a high frequency to the pair of electrodes performed with the pair of electrodes maintained at the same position as the first step,
• wherein the heating time in the first step and that in the second step are independently controlled.

11:

• The spot-welding method for metallic materials according to claim 10, wherein
• the inside of the given region of the metallic materials is heated by the first heating means,
• a proximity of the given region of the metallic materials is heated by the second heating means, and
• the heating by the first heating means and that by the second heating means are independently controlled.

12:

• The spot-welding method for metallic materials according to claim 11, wherein
• the given region heated by the first heating means is the internal area of a circle defined by projecting the cross-sectional area of the electrodes on the metallic materials,
• the different region heated by the second heating means is a ring-shaped proximity region along the circle defined by projecting the cross-sectional area of the electrodes on the metallic materials, and
• the heating by the first heating means and that by the second heating means are independently controlled.

15:

• A method for spot-welding metallic materials, comprising:
• a first step for sandwiching the metallic materials with a pair of electrodes;
• a second step for heating and spot-welding a given region of the metallic materials by applying electric power for welding to the pair of electrodes;
• and
• a third step for heating the welded given region of the metallic materials or a region different from the given region which should be welded by applying electric power having a high-frequency to the pair of electrodes, wherein
• the heating time in the second step and that in the third step are independently controlled.

16:

• A method for spot-welding metallic materials, comprising:
• sandwiching the metallic materials with a pair of electrodes;
• a welding step for heating and spot-welding a given region of the metallic materials by applying electric power for welding to the pair of electrodes;
• and
• a heat-treating step for heating the welded given region of the metallic materials or a region different from the given region which should be welded by applying electric power having a high frequency to the pair of electrodes,
• wherein the heating time in the welding and that in the heat treating step are independently controlled, and
• wherein a heating time and a power of the high frequency are controlled.

18:

• A method for spot-welding metallic materials, comprising:
• sandwiching the metallic materials with a pair of electrodes;
• a pre-heating step for pre-heating a region different from a given region which should be welded by applying electric power having a high frequency to the pair of electrodes;
• and
• a welding step for spot-welding a given region of the metallic materials by applying electric power for welding to the pair of electrodes, wherein
• the heating time in the pre-heating step and that in the welding step are independently controlled.

21:

• A method for spot-welding metallic materials, comprising:
• sandwiching the metallic materials with a pair of electrodes;
• a welding step for heating a given region of the metallic materials which should be welded by applying electric power for welding to the pair of electrodes;
• and
• a heating step for heating a region different from the region in of the metallic materials which should be welded by applying electric power having a high frequency to the pair of electrodes,
• wherein the heating time in the welding step and that in the heating are independently controlled, and
• wherein the electric power for welding is applied to the pair of electrodes and the high-frequency power is superimposed to the pair of electrodes by controlling the heating time and the power.