Forging is more than a shape-making process. It is an acceptedfact that the titanium alloys and advanced superalloys used in aircraft manufacture today are structure sensitive; second-tier mechanical properties, those that affect the actual service life of the hardware produced, are the most structure sensitive. The author claims that it is possible to control microstructure on a production basis, and examines the factors that must be controlled. For titanium alloys, the key is the (α+β)/β transformation, of or the nickel-base superalloys, control is based upon the y'phase and its solutioning range.
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