A method of fusion welding two ferrous alloy component parts, at least one of which is considered unweldable, involves placing a low carbon steel band into a groove defined in part by each of the ferrous alloy component parts and then conveying a concentrated energy source along a welding line that overlaps the low carbon steel band to melt the steel band along with adjacent portions of the ferrous alloy component parts to form a blended alloy weld pool. The blended alloy weld pool solidifies behind the forward movement of the concentrated energy source into a weld joint that fusion welds the ferrous alloy component parts together. The ferrous alloy component parts may include a differential casing and a ring gear. In that regard, a differential casing and ring gear assembly that includes a weld joint is also disclosed.

A laser welding method for joining a non-sintered material to a sintered material is disclosed. The method includes the steps of providing a first component made of a non-sintered material, providing a second component made of a sintered material, arranging the first component and the second component along a contact plane to produce a joining joint, applying a laser beam to a first joining region of the first component in the region of the joining joint to melt the first joining region to a melt, melting a second joining region of the second component in the region of the joining joint by means of the melt of the first joining region, and cooling the joining joint.

A scanner controller analyzes a position instruction in which a position in a world coordinate system and a position in a local coordinate system of a path of laser light are associated with each other and creates a movement command for a drive unit of a scanner based on the position of the local coordinate system. Further, the scanner controller calculates the current position of the scanner in the local coordinate system based on the position and attitude of a robot in the world coordinate system and the position in the world coordinate system in accordance with the position instruction. When the distance between the calculated position of the local coordinate system and the position in the local coordinate system in accordance with the position instruction is below a predetermined threshold, the scanner controller then determines to start machining and performs control of a drive unit of the scanner.

A damper for suppressing vibrations of a crankshaft of a vehicle is disclosed. The damper comprises a hub having a circular wall extending about a rotational axis to define a bore formed therethrough. The wall comprises a step portion radially extending therefrom and having a first arcuate portion formed thereon. The hub comprises a body portion radially extending from the wall to a lip to define an open cavity. The damper comprises a weld nugget disposed between the hub and the plate. The weld nugget has a root extending therethrough concurrent with the rotational axis to join the hub and the plate. The root has tip defining a profile such that the hollow channel is disposed at an angle tangent to the profile to lessen cracking due to stress.

A laser-welded lap joint includes a weld zone formed by joining a plurality of steel sheets one over another together by laser welding. The weld zone has a J shape and includes a main weld zone having a linear weld line shape and a weld terminal end zone having an arcuate or circular weld line shape. The length L.sub.1 of the main weld zone is ⅔ or more and ⅘ or less of the full length L of the weld zone represented by formula (1). The radius R of the weld terminal end zone satisfies formula (2). The angle θ of the weld terminal end zone satisfies formula (3). The total size of a gap between the plurality of steel sheets in a lapped portion is 0% or more and 15% or less of the total thickness of the plurality of steel sheets.

A laser welding system for sealing welding a cell top cover includes a laser emitting device for generating a scanning welding laser beam to be irradiated to a portion of the cell top cover to be welded, and a control device for controlling the laser emitting device to perform continuous scanning sealing welding on the cell top cover. The laser welding system is configured to complete the sealing welding of the cell top cover at only one work station.

Laser welding methods include focusing laser radiation onto a first metal sheet disposed on a metal part, optionally with one or more intervening metal sheets therebetween. The laser radiation is steered to trace at least one spiral path to spot-weld together the metal parts. The laser radiation includes a center beam and an annular beam to maintain a stable keyhole. One method is tailored to weld aluminum parts, e.g., with high gas content and/or dissimilar compositions, and the laser radiation traces first an outward spiral path and then an inward spiral path. The center beam is pulsed during one segment of the inward spiral path. Another method is tailored to weld steel or copper parts having a coating at an interface therebetween, and the laser radiation traces an inward spiral path. The interface may be a zero-gap interface, or a non-zero gap may exist.

Laser welding methods include focusing laser radiation onto a first metal sheet disposed on a metal part, optionally with one or more intervening metal sheets therebetween. The laser radiation is steered to trace at least one spiral path to spot-weld together the metal parts. The laser radiation includes a center beam and an annular beam to maintain a stable keyhole. One method is tailored to weld aluminum parts, e.g., with high gas content and/or dissimilar compositions, and the laser radiation traces first an outward spiral path and then an inward spiral path. The center beam is pulsed during one segment of the inward spiral path. Another method is tailored to weld steel or copper parts having a coating at an interface therebetween, and the laser radiation traces an inward spiral path. The interface may be a zero-gap interface, or a non-zero gap may exist.

A metal member includes a first plate, and a second plate abutting against and welded to the first plate in at least one butt portion. In the butt portion, a length from a first end to a second end of a welding boundary line between the first plate and the second plate is longer than a length of a straight line connecting the first end to the second end of the welding boundary line.

A metal member includes a first plate, and a second plate abutting against and welded to the first plate in at least one butt portion. In the butt portion, a length from a first end to a second end of a welding boundary line between the first plate and the second plate is longer than a length of a straight line connecting the first end to the second end of the welding boundary line.