Patent ID: 6140601
Filing Date: 2000-10-31
Classification: B21C,B23K,Y10S

Abstract:
A laser-welded steel pipe having a weld zone comprising:a steel pipe consisting essentially of C in an amount of 0.01 to 0.2 wt. %; Si, said Si being in an amount of 1 wt. % or less; Mn in an amount of 0.05 to 2 wt. % and Cr in an amount of 6 wt. % or less; said weld zone having a melted and solidified metal structure; said melted and solidified metal structure containing carbon and oxygen, the carbon content in wt. %, and the oxygen content in wt. % in the melted and solidified metal structure satisfying the following equations:(carbon wt. %).times.(oxygen wt. %).ltoreq.0.006for a steel pipe containing carbon in an amount of less than 0.2 wt. %, and(oxygen weight %).gtoreq.0.02.