A heat treatment furnace and a method for heat treatment of a steel sheet blank is disclosed having at least one furnace chamber and a transport system for conveying the steel sheet blanks through the furnace chamber. A preheating chamber, a metallurgical bonding path and a cooling chamber, wherein the steel sheet blank can be heated in the preheating chamber to a temperature of above 200° C. A method for the production of a hot-formed and press-quenched motor-vehicle part is also disclosed.