A rotor assembly for an electric device includes a laminated stack of electric steel sheets defining a plurality of longitudinally extending grooves. A conductor bar is disposed within each of the grooves. Each of the conductor bars includes a first end and a second end extending longitudinal outward from opposing axial end surfaces of the laminated stack. The first end and the second end of the conductor bars include a textured surface having micro-sized surface irregularities. A first end ring is cast in place over the first ends of the conductor bars, and a second end ring is cast in place over the second ends of the conductor bars. The textured surface in the first ends and the second ends of the conductor bars mechanically interlocking with the cast in place first end ring and second end ring respectively.