Recrystallization textures in tantalum sheet and wire C.L. Briant a, * , E. MacDonald a , R.W. Balliett b , T. Luong b a Division of Engineering, Brown University, Providence, Rhode Island 02912, USA b H.C. Starck, Inc., 45 Industrial Place, Newton, MA, USA Received 8 March 1999; accepted 16 August 1999 Abstract This paper presents a study of the evolution of recrystallization texture in tantalum. Both rolled sheet and drawn wire are considered. The rolled product developed a recrystallized texture in which the rolling plane normal was parallel to h111i. There was no speci®c direction parallel to the rolling direction; rather this direction varied so that the rolling plane orientation could be ac- commodated. In the drawn wire, the recrystallized texture was one in which h110i was parallel to the deformation direc- tion. Ó 2000 Elsevier Science Ltd. All rights reserved. Keywords: Tantalum; Texture; Recrystallization; EBSP 1. Introduction Although in many cases polycrystalline, body-cen- tered-cubic (bcc) materials show reasonably isotropic mechanical properties, they can, through repeated de- formation, become highly textured. The presence of this texture means that mechanical test samples cut out of the deformed piece will have varying mechanical prop- erties that depend on the orientation of the test sample relative to that of the original piece. Production of wire and sheet products requires repeated deformation and is almost always accompanied by the development of a strong texture. Recrystallization of the worked material will not necessarily remove this texture, since research has shown that recrystallized samples may retain the texture of the worked material or develop a completely dierent texture through the formation and growth of new grains [1]. Furthermore, the amount of deformation that the sample receives may aect the sharpness and orientation of the texture that forms during recrystalli- zation. This paper reports a study of the recrystallization texture of tantalum. This material was processed from ingot to either a sheet or wire product. Samples were collected at various points during the process so that the evolution of the texture could be followed. The results show that a strong texture is formed in the recrystallized sheet material in which the rolling plane is parallel to the f111g plane in the material. There is not a pre- ferred direction parallel to the rolling direction. The recrystallization texture increases in sharpness as the deformation continues. In the wire product the recrys- tallization texture is similar to the traditional bcc wire texture with h110i parallel to the drawing direction. However, this texture is not as strong as that in the sheet material. 2. Experimental All of the samples used in this study were prepared by H.C. Starck. The material began as two cylindrical in- gots that had been prepared by the process outlined in Fig. 1(a). The original powder and recycled material was ®rst electron beam melted. These ingots were forged and then vacuum arc re-melted to produce the starting ma- terial. Their chemistries are given in Table 1. Before any processing was performed, samples were taken from the bottom and the top of each ingot in the manner depicted in Fig. 2. Eight samples were collected that covered the diam- eter from one edge to another. As shown in the ®gure, they were taken so that the direction of growth of the columnar grains could be examined. In addition, each ingot was cut into two pieces and an additional set of eight samples was taken from one of these cut faces. International Journal of Refractory Metals & Hard Materials 18 (2000) 1±8 * Corresponding author. Fax: +1-401-863-1157. 0263-4368/00/$ - see front matter Ó 2000 Elsevier Science Ltd. All rights reserved. PII: S 0 2 6 3 - 4 3 6 8 ( 9 9 ) 0 0 0 2 8 - 1