| 摘要 |
PURPOSE: A method of welding hot stamping steel sheets is provided to secure tensile strength of a welded portion by pre-treating and removing an Al-Si coating layer through a laser ablation process along a welding line and then performing laser welding. CONSTITUTION: A method of welding hot stamping steel sheets comprises the steps of: aligning the front faces of coating boron steel sheets(P1,P2) and arranging the coating boron steel sheets on a jig(10) with the front faces facing upward(S1), performing a laser ablation process using a laser beam along a welding line on the front face of each coating boron steel sheet held on the jig to remove the coating layer around the front welding line of each coating boron steel sheet(S2), aligning the rear faces of the coating boron steel sheets and arranging the coating boron steel sheets with the rear faces facing upward(S3), performing a laser ablation process using a laser beam along a welding line on the rear faces of the coating boron steel sheets held on the jig to remove the coating layer around a the welding line on the rear faces of the coating boron steel sheets(S4), lowering the thinner coating boron steel sheet relative to the thicker coating boron steel sheet on the jig by the thickness difference so that the front faces of the coating boron steel sheets become flush with each other(S5), and performing butt laser welding irradiating the welding line of the rear face of each coating boron steel sheet with a laser beam(S6). |
