Joint structure

A joint structure comprising:

• a first material of metal;
• a second material of metal weldable to the first material;
• and
• a different material including a penetrating part, the different material being sandwiched between the first material and the second material, the different material being different from the first material and the second material and being difficult to weld to the first material and the second material, wherein
• the different material is compressed between the first material and the second material and is fixed to the first material and second material, and
• the first material is bonded to the second material via the penetrating part by fusion bonding that is caused by laser light which is incident to the first material under conditions in which:
• (i) the first material is disposed on a side on which the laser light is incident in a plate thickness direction of an incident region of the first material, the incident region being a region in which the laser light emitted toward the penetrating part is incident;
• (ii) a first gap is provided between the first material and the second material in the plate thickness direction before welding;
• and
• (iii) the first gap having a length in the plate thickness direction, the length of the first gap being determined in relation to a plate thickness of the first material,
• wherein the length of the first gap in the incident region is not less than 6% and not more than 38% of the plate thickness of the first material in the incident region,
• wherein the incident region in which laser light is incident in the plate thickness direction is smaller than the penetrating part,
• a second gap is provided between the incident region and the penetrating part, and
• wherein the different material is a resin, and the second gap has a length not less than 200% of the length of the first gap.

A joint structure comprising:

• a first material of metal;
• a second material of metal weldable to the first material;
• and
• a different material including a penetrating part, the different material being sandwiched between the first material and the second material, the different material being different from the first material and the second material and being difficult to weld to the first material and the second material, wherein
• the different material is compressed between the first material and the second material and is fixed to the first material and second material, and
• the first material is bonded to the second material via the penetrating part by fusion bonding that is caused by laser light which is incident to the first material under conditions in which:
• (i) the first material is disposed on a side on which the laser light is incident in a plate thickness direction of an incident region of the first material, the incident region being a region in which the laser light emitted toward the penetrating part is incident;
• (ii) a first gap is provided between the first material and the second material in the plate thickness direction before welding;
• and
• (iii) the first gap having a length in the plate thickness direction, the length of the first gap being determined in relation to a plate thickness of the first material,
• wherein the length of the first gap in the incident region is not less than 6% and not more than 38% of the plate thickness of the first material in the incident region,
• wherein the incident region in which laser light is incident in the plate thickness direction is smaller than the penetrating part,
• a second gap is provided between the incident region and the penetrating part, and
• wherein the different material is a fiber-reinforced resin, and the second gap has a length not less than 150% of the length of the first gap.

A joint structure comprising:

• a first material of metal;
• a second material of metal weldable to the first material;
• and
• a different material including a penetrating part, the different material being sandwiched between the first material and the second material, the different material being different from the first material and the second material and being difficult to weld to the first material and the second material, wherein
• the different material is compressed between the first material and the second material and is fixed to the first material and second material, and
• the first material is bonded to the second material via the penetrating part by fusion bonding,
• the different material flows and clings to an outer edge of a weld part at which the first material and the second material are fused and bonded together,
• the fusion bonding is caused by laser light which is incident to the first material under conditions in which:
• (i) the first material is disposed on a side on which the laser light is incident in a plate thickness direction of an incident region of the first material, the incident region being a region in which the laser light emitted toward the penetrating part is incident;
• and
• (ii) a first gap is provided between the first material and the second material in the plate thickness direction before welding,
• wherein the different material is a resin material, and
• a second gap is provided between the incident region and the penetrating part.