UVパルスレーザテクスチャリングによるA5052アルミニウム合金の接着性向上に関する表面改質

抄録

We subjected an A5052 aluminum alloy sample to a dry and rapid surface treatment using 355-nm pulsed laser irradiation, and measured the effects of surface modification. We varied the laser irradiation pitch and found the processed surfaces to have an irregular and complicated topography up to a depth of about 5 μm. X-ray photoelectron spectroscopy (XPS) analysis of the material surfaces revealed that Al₂O₃ with a binding energy of 74 eV was formed regardless of laser irradiation, and that increased irradiation density accelerates surface oxidation. While the non-laser-irradiated areas exhibited hydrophobicity, laser-irradiated regions became superhydrophilic with a contact angle of less than 5°. We performed tensile shear tests on lap joint specimens produced at a beam scanning speed of 500 mm/s and a laser irradiation pitch of 5 μm, and obtained a joint strength of 10 MPa. These results indicate that UV pulsed laser irradiation is effective for fast surface modification.