Patent ID: 6141974
Filing Date: 2000-11-07
Classification: B22F,C21D,C22C

Abstract:
A process for treating carbide metal items which comprises:holding a carbide metal item at a sustained temperature in the range of -20.degree. F. to -80.degree. F. for a period of at least 2 hours;applying gaseous nitrogen to said metal to lower, at a rate no faster than 3.degree. F. per minute, its temperature to within the range of -300.degree. F. to -320.degree. F.holding said temperature for a period of 2 to 24 hours;elevating the temperature of said carbide item to within the range of -80.degree. F. to -20.degree. F. and holding said temperature for a period of 2-24 hours;elevating the temperature of said carbide item to within the range of 300.degree. F. to 500.degree. F. for a period of about one hour; andallowing the temperature of the carbide metal item to return to ambient temperature.