Patent ID: 6261701
Filing Date: 2001-07-17
Classification: B23K,Y10T

Abstract:
A welded work piece comprising:a first blank of steel sheet stock having a pair of exterior surfaces with a first thickness of between approximately 0.50 and 0.75 millimeters and having at least one first precision sheared edge;a second blank of steel sheet stock having a pair of exterior surfaces with a second thickness different than the first thickness of between approximately 1.25 and 1.50 millimeters and having at least one second precision sheared edge;a laser welded seam permanently joining the respective first and second precision sheared edges;wherein the respective first and second precision sheared edges of the respective first and second blanks are aligned to form a minimized gap therebetween of between approximately zero and 0.8 millimeters before being welded;and wherein the laser welded seam is formed with a beam from a continuous wave Nd-YAG laser, the beam being at a compound angle to the minimized gap and having a leading angle .theta. of between approximately 5 and 15 degrees and a leaning angle .gamma. of between approximately 1 and 10 degrees;and wherein the beam is focused substantially into an elliptical shaped spot about the minimized gap and approximately 70 to 85 percent of the cross-sectional area of the beam is incident on the first blank;whereby the welded seam has a tensile strength exceeding approximately 9,000 pounds per square inch.