LASER WELDING METHOD
FIG2 are process explanatory views of the laser welding method  FIG2 are process explanatory views of the laser welding method  FIG2 are process explanatory views of the laser welding method
More specifically, first, the pair of separators 11 and 12 are stacked on each other, and then the separators 11 and 12 are irradiated with a laser beam (first irradiation) to form the welded portion L1, i.e., the welded seal 14, of the separators 11 and 12 as illustrated in FIG2(A). Subsequently, as illustrated in FIG2(B) and 2(C), the accessory component 20 is stacked on the pair of welded separators 11 and 12, and then the separators 11 and 12 and the accessory component 20 are irradiated with a laser beam (second irradiation) to form the welded portion L2 of the accessory component 20. When the separators 11 and 12 and the accessory component 20 are welded, the welded portion L2 of the accessory component 20 is reciprocatingly irradiated with laser along a fixed welding line. Herein, the description "the welded portion L2 of the accessory component 20 is reciprocatingly irradiated with laser along a fixed welding line" means that the irradiation is performed twice (one reciprocation) along the fixed welding line. However, when the start end and the termination end of the irradiation are set at the same position while overlapping each other on the plane, a state where the density of the energy to be emitted becomes excessively high is caused, so that a defect, such as a hole, occurs in some cases as described above. First scanning of second irradiation (forward scanning, FIG2(B)) Second scanning of second irradiation (return scanning, FIG2(C))  More specifically, first, the pair of separators 11 and 12 are stacked on each other, and then the separators 11 and 12 are irradiated with a laser beam (first irradiation) to form the welded portion L1, i.e., the welded seal 14, of the separators 11 and 12 as illustrated in FIG2(A). Subsequently, as illustrated in FIG2(B) and 2(C), the accessory component 20 is stacked on the pair of welded separators 11 and 12, and then the separators 11 and 12 and the accessory component 20 are irradiated with a laser beam (second irradiation) to form the welded portion L2 of the accessory component 20. When the separators 11 and 12 and the accessory component 20 are welded, the welded portion L2 of the accessory component 20 is reciprocatingly irradiated with laser along a fixed welding line. Herein, the description "the welded portion L2 of the accessory component 20 is reciprocatingly irradiated with laser along a fixed welding line" means that the irradiation is performed twice (one reciprocation) along the fixed welding line. However, when the start end and the termination end of the irradiation are set at the same position while overlapping each other on the plane, a state where the density of the energy to be emitted becomes excessively high is caused, so that a defect, such as a hole, occurs in some cases as described above. First scanning of second irradiation (forward scanning, FIG2(B)) Second scanning of second irradiation (return scanning, FIG2(C))  More specifically, first, the pair of separators 11 and 12 are stacked on each other, and then the separators 11 and 12 are irradiated with a laser beam (first irradiation) to form the welded portion L1, i.e., the welded seal 14, of the separators 11 and 12 as illustrated in FIG2(A). Subsequently, as illustrated in FIG2(B) and 2(C), the accessory component 20 is stacked on the pair of welded separators 11 and 12, and then the separators 11 and 12 and the accessory component 20 are irradiated with a laser beam (second irradiation) to form the welded portion L2 of the accessory component 20. When the separators 11 and 12 and the accessory component 20 are welded, the welded portion L2 of the accessory component 20 is reciprocatingly irradiated with laser along a fixed welding line. Herein, the description "the welded portion L2 of the accessory component 20 is reciprocatingly irradiated with laser along a fixed welding line" means that the irradiation is performed twice (one reciprocation) along the fixed welding line. However, when the start end and the termination end of the irradiation are set at the same position while overlapping each other on the plane, a state where the density of the energy to be emitted becomes excessively high is caused, so that a defect, such as a hole, occurs in some cases as described above. First scanning of second irradiation (forward scanning, FIG2(B)) Second scanning of second irradiation (return scanning, FIG2(C))
process views
2
same welding line.
20
accessory component
12
separators
11
separators
['6. The laser welding method according to Claim 3 or 5, wherein the first and second workpieces are fuel cell separators, and the third workpiece is an accessory component attached to the fuel cell separator.']