Vehicle drivetrain assembly and method for making the assembly

A method for making a vehicle drivetrain assembly comprising:

• positioning an annular planar plate portion of an aluminum torque transmitting member having a first round opening with a central axis in a spaced relationship adjacent an annular connection location of a steel torque transmitting member with the annular connection location facing axially relative to the central axis and extending around the opening of the aluminum torque transmitting member, wherein the aluminum torque transmitting member is a clutch hub or housing including an annular wall circumferentially-extending around the planar plate portion and having an axially extending spline portion, and further wherein the steel torque transmitting member is a sun gear, a ring gear, a torque transmitting hub, or a shaft, and has a second round opening through which the central axis extends;
• and
• progressively applying an electromagnetic pulse weld along a radially outward direction relative to the central axis of the assembly to form and weld the plate portion of the aluminum torque transmitting member to the connection location of the steel torque transmitting member, wherein the radially outward direction extends along a direction extending from a radially inner surface of the steel torque transmitting member toward a radially outer surface of the steel torque transmitting member.