Accession Number : AD0623399

Title :   X-RAY STUDY OF WIRE-DRAWN NIOBIUM AND TANTALUM.

Descriptive Note : Technical rept.,

Corporate Author : MARTIN CO ORLANDO FLA MATERIALS RESEARCH LAB

Personal Author(s) : Adler,R. P. I. ; Otte,H. M.

Report Date : SEP 1965

Pagination or Media Count : 32

Abstract : Deformation, introduced into Niobium (Nb) and Tantalum (Ta) specimens by wire drawing at room temperature, produced changes in the shape and position of X-ray diffraction peaks. The resultant peak profiles and locations of all available peaks were recorded using the DebyeScherrer geometry on a modified diffractometer with crystal monochromated CuK alpha sub 1 radiation. The amount of deformation in the surface layers of both metals was found to saturate essentially after only 20 percent reduction in area. The measured decrease in the lattice parameters of either material was attributed to a residual surface stress; the average value for the deformed saturated state for both Ta and Nb wires corresponded to an equivalent longitudinal tensile stress of 35 = 5 kg. per sq. mm. Integral breadth measurements revealed approximately equal X-ray particle sizes in the <100> and <110> directions; the minimum particle size for the microstructures of both metals was around 200A and occurred after the first few draws. (Author)

Descriptors :   (*NIOBIUM, DEFORMATION), (*TANTALUM, DEFORMATION), X RAY DIFFRACTION, DRAWING(FORMING), CRYSTAL DEFECTS, STRESSES, STRAIN(MECHANICS)

Distribution Statement : APPROVED FOR PUBLIC RELEASE