Physical Metallurgy of Uncommon Metals

The solid solubility limits of the miscibility gap in the U-Nb phase diagram were determined between 800 and 1000 deg C by analysis of diffusion couples using an electron microbeam probe technique. The feasibility of using xray-diffraction methods to measure residual stresses in U and Zr (Zircaloy-2) was investigated. The magnetic properties of hematite ( alpha -Fe/sub 2/O/sub 3/ ) were investigated. The crystal structures of Y/sub 5/Si/sub 3/ and Y/sub 5/Ge/ sub 3 are being investigated. The structural relationships in the pseudo binary system ZrFe/sub 2/ -ZrC r/sub 2/ were studied. (W.L.H.

PHYSICAL METALLURGY OF UNCOMMON METALS

Incremental couples at 10% intervals across the U-Nb binary system were prepared and diffused. Irradiation damage of nickel single crystals bombarded with 3-Mev electrons from a Van de Graaff generator were studied by Kossel line techniques. It was concluded that most defects anneal out below room temperature and all anneal out below 400 deg C. The cold-rolled texture of tantaium is described by (200) and (110) pole figures. This texture may be approximated by the ideal orientations, {112} , {100{ , and {111} . The directionality of Young's modulus, yield strength, and tensile strengih of tantalum is also presented. The effects of thermal gradients on the transformation kinetics and diffusion in U--10 wt.% Mo were investigated. The alloy U(Fe,Mn) was found to be paramagnetic from 480 to 10 deg K. The remanent magnetization of hematite along particular directions in the (111) plane and along the STA111! direction of a rectangular prism was measured during a complete cycle of temperature chsnge between 488 and 77 deg K. The remanent-temperature relationship snd the thermal hysteresis effect were also measured. The concept of space filling was developed for presenting geometrical relationships of different crystal structures. The structure of the pseudo-binary system ReTi/sub 2/--TiSi/sub 2/ was investigated. (M.C.G.