Claims
- 1. A method for hot working materials selected from the group consisting of iron base superalloys, nickel base superalloys, cobalt base superalloys, titanium alloys, tool steels and refractory metals, which comprises hot working the material using dies which have been heated to the working temperature using a deformation rate which is adjusted so that the energy input the workpiece is substantially constant with respect to time.
- 2. A method as in claim 1 in which the load applied to the material and the deformation of the material are integrated to produce an output signal which is proportionate to the energy input, said output signal being used to control the subsequent deformation of the material.
- 3. A method as in claim 1 in which the deformation is controlled by a preprogrammed controller so that the deformation proceeds at a constant energy rate.
- 4. A method as in claim 1 in which the energy input to the forming apparatus is monitored and controlled in such a fashion that the energy input to the material is maintained at a constant rate.
- 5. In a method for hot working nickel base superalloy articles which comprises hot working the articles using dies which have been heated to the working temperature at a constant strain rate for an initial amount of from about 0.2 to about 10% strain and subsequently working the articles under conditions of constant energy input.
- 6. In an apparatus for hot working metal articles, the improvement which comprises stress sensing means, strain sensing means, and control means which integrate the prior stress and strain history of the material and controls this subsequent working of the material so that said subsequent working occurs under condition of constant energy input to the article.
Government Interests
The Government has rights in this invention pursuant to Contract No. F49620-80-C-0004 awarded by the Department of the Air Force.
US Referenced Citations (22)