| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a laser building-up welding method, by which defects generated in a built-up weld layer of a valve seat of a cylinder head is further inhibited. <P>SOLUTION: A laser building-up welding method is executed by annularly moving a laser irradiation position P along a valve seat 16, while forming a built-up weld layer on the laser irradiation position P by irradiating the valve seat 16 of a cylinder head 12 with a laser beam 20 while supplying a copper alloy powder 18. Further, the laser building-up welding method is executed as follows: a start end part 50 of building-up welding is formed by increasing an output W of the laser beam 20 according to a supply amount S of the copper alloy powder 18 while gradually increasing the supply amount S of the copper alloy powder 18 at the start of the building-up welding; an ordinary part 51 of building-up welding is formed while keeping constant the supply amount S of the copper alloy powder 18 and the output W of the laser beam 20; a terminal end part 52 of building-up welding is formed by increasing the output W of the laser beam 20 to a predetermined output Wb while keeping constant the supply amount S of the copper alloy powder 18, from the position before the start end part 50; and the terminal end part 52 is overlapped on the start end part 50. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
