STRENGTHENING OF CHROMIUM-MAGNESIA COMPOSITES.
Abstract
An evaluation was made of the notch sensitivity of Chrome-30, an extruded Cr-base composite containing 6% MgO and 0.5 wt % Ti. On the basis of tensile data, no notch sensitivity problems were indicated with the notches investigated, which ranged in severity up to a stress concentration factor of 8.2. Several process and compositional variations were studied for maximizing ductility. Best results were obtained with a composite consisting of Cr + 2 wt. % MgO. This compound exhibited an average room temperature tensile elongation of 50% which was more than twice that of Chrome-30. The strengths of the two materials were similar. Solid solution strenthening of the Cr + 2 wt. % MgO composite was successfully attempted with Cb additions. Columbium levels as low as 1 wt. % produced over twofold increases in strength at 2400 F although room temperature ductility for these alloys was low. Studies of alloy homogenization, oxidation/nitridation resistance, microstructure, impact strength, and various annealing schedules are also described in detail. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1963
- Accession Number
- AD0424854
Entities
People
- G. C. Reed