I've heard stories about T-34's and KV's ramming enemy tanks. It probably happened in a life or death situations (facing a heavier tank, ran out of ammo, turret ring jammed, engine on fire, brakes damaged...), but I doubt it was common practise. Wasn't limited to the Soviets either.
Anyway, about this ingame... no. Immobilising vehicles is one of those annoying abilities we like to keep limited to the PE ATHT. Also, with tanks phasing through each other I think it would look rather ugly.