Microstructure and mechanical properties of HE-treated titanium depending on its initial state
|Krzysztof Topolski 1, Halina Garbacz 1, Waclaw Pachla 2, Krzysztof J. Kurzydlowski 1|
1. Warsaw University of Technology, Faculty of Materials Science and Engineering (InMat), Wołoska 141, Warszawa 02-507, Poland
The study was concerned with examining the properties of titanium subjected to hydrostatic extrusion (HE) which is classified among the methods of severe plastic deformation (SPD). In our earlier studies we used hydro-extrusion for producing nano-crystalline titanium with the mechanical properties comparable with those of the binary Ti6Al4V titanium alloy [1-3]. The aim of the present work was to find how the microstructure of titanium in its initial state (prior to HE) would affect the effectiveness of the hydroextrusion process. The measure of this effectiveness was taken to be the disintegration degree of the microstructure and the mechanical properties of the titanium rods thus produced. The results obtained will permit optimizing the process of hydrostatic extrusion of titanium. The titanium rods examined had average grain sizes of 15µm and 160µm and differed in their mechanical properties. The rods were subjected to many-stage extrusion so as to achieve a true strain of 3.79. The mechanical properties of the materials were estimated by examining their microstructure and subjecting them to static tensile tests. The grain size was analyzed by scanning electron microscopy. It has been found that, in the materials examined, the microstructure of titanium in the initial state does not affect the course of the hydrostatic extrusion process. Irrespective of their initial microstructure, the HE-treated titanium rods had similar grain sizes of about 60nm and were characterized by similar mechanical properties. 1)Kurzydlowski K.J.:Materials Science Forum, 503-504 (2006) p.341-348. 2)Garbacz H., Lewandowska M., Pachla W., Kurzydlowski K.J.:Journal of Microscopy. Vol.223, Pt 3 September 2006, p.272-274. 3)Topolski K., Garbacz H., Pachla W., Kurzydlowski K.J.:Advances in Materials Science No.4 (2007)-in press.
Presentation: Poster at E-MRS Fall Meeting 2007, Acta Materialia Gold Medal Workshop, by Krzysztof Topolski
See On-line Journal of E-MRS Fall Meeting 2007
Submitted: 2007-07-17 13:17 Revised: 2009-06-07 00:44