A non-magnetic mono-component toner of the present invention comprises, at least, a plurality of mother particles and a plurality of CCA particles adhering to the mother particles. A portion of projected streaks on the friction joining steel plate is designed to have a Vickers hardness at least 3 times greater than the surface of the steel products, which allows the projected streaks to more easily enter the steel products thereby increasing the friction coefficient between the steel products. A historical rate at which the computer system has transitioned between the first and second operating modes is determined, and the requested transition is permitted in response to the historical rate being less than a first preselected setpoint, but denied in response to the historical rate being greater than the first preselected setpoint.