Laser joining for different materials between 1050 aluminum alloy plate of 1 mm thickness and polypropylene sheet of 2 mm thickness using a newly developed insert sheet was studied. The diode laser-irradiation to the polypropylene side was carried out in air. The effects of an anodizing onto the aluminum specimens on the joining properties were examined.
It was not possible to join the 1050 aluminum plate to polyethylene sheet directly under the various laser-irradiation conditions. However, the use of insert sheet held between the aluminum plate and the polypropylene sheet made it possible to join the 1050 aluminum plate to polyethylene sheet by laser-irradiation. The joining strength increased with the increase in the input energy by laser-irradiation, and the anodizing for 1050 aluminum plate improved the joining strength. It was found that the chemical state of aluminum surface strongly affected the joining strength.
