Patent ID: 8250890

Claim:
A method of increasing the adhesion of a lubricant to at least one metal workpiece for subsequent hot forming of the metal workpiece, the method comprising: applying lubricant particles dispersed in a liquid carrier to a surface of at least one metal workpiece and removing the liquid carrier to form a lubricant film over the metal workpiece surface, wherein the lubricant film consists of particles of at least one of boron nitride, graphite, WS 2 , or MoS 2 , and wherein the lubricant film of the particles has a predetermined thickness of up to about 100 micrometers; positioning the metal workpiece in a humidified air chamber; exposing the metal workpiece in the chamber to a predetermined level of relative humidity of about 50 percent to about 100 percent, for a predetermined humidification period of time of at least one day, and at a predetermined humidification temperature, comprising selecting the predetermined level of humidity, humidification time, and temperature to increase the adhesion of the lubricant film of the particles to the metal workpiece; removing the metal workpiece from the chamber; and thereafter heating the metal workpiece for a hot forming operation on the lubricated surface of the metal workpiece.