THE DEVELOPMENT OF OPTIMUM MANUFACTURING METHODS FOR COLUMBIUM ALLOY FORGINGS
Abstract
Sixteen Cb74 (10W-4Zr) closed die forgings were made from 16 forging blanks with conventional forging equipment and techniques. No perceptible die wear resulted with a 2400F forging temperature while considerable die wear occurred when a 2200F forging temperature was used. Excellent oxidation protection was provided by the Al-CrSi coating. Variation in the thickness of this coating is believed to have caused the slightly rough surface on several forgings. Open die side forging of extruded and annealed Cb74 to a smaller round produced center bursts. This defect was not encountered when the stock was swaged or flattened. The high temperature tensile and stress rupture strengths of the 4% Zr closed die forgings were equivalent to that reported for 6% Zr Cb74 upsets. Room temperature and -40F tensile ductility was excellent in the longitudinal direction but the transverse room temperature ductility was low. Oxidation resistance of the 4% Zr Cb74 was the same as the 6% Zr alloy in the 2000 to 2400 F range but was superior in the 1500 to 1823 F range.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1961
- Accession Number
- AD0273543
Entities
People
- P.f. Darby