Abstract In a procedure in which a body formed of an iron-based alloy is manufactured from powder by isostatic compression, the powder is placed in a flexible container and subjected to isostatic pressure and heat. The isostatic hot pressing is carried out at two temperatures, at one of which the iron-based alloy is at least 25 percent in Alpha -phase and at the other of which the iron-based alloy is in gamma -phase. If the treatment at the temperature for gamma -phase is carried out first, the body is cooled below the temperature level at which it is at least 25 percent in Alpha -phase to prevent retention of the gamma phase and then raised to the temperature at which it is at least 25 percent in Alpha -phase.
Method according to claim 1, which comprises carrying out the isostatic hot pressing first at the temperature level in which the iron-based alloy is at least up to 25 PERCENT in Alpha -phase and then at the temperature level in which the iron-based alloy is in gamma -phase.
Claim 2
Dependent Claim
79 words
Method according to claim 1, which comprises carrying out the isostatic hot pressing first at the temperature level in which the iron-based alloy is in gamma -phase and then at the temperature level in which the iron-based alloy is at least up to 25 percent in Alpha -phase, and which includes lowering the temperature after the treatment at the first-mentioned temperature level to a value below the last-mentioned temperature level and thereafter raising it to the last-mentioned temperature level.