Author(s)

B.J. Kooi, Y.T. Pei & J.Th.M. De Hosson

Abstract

Microstructural features in a laser clad TiB-Ti composite coating B.J. Kooi, Y.T. Pei & J.Th.M De Hosson Department of Applied Physics, Materials Science Center and Netherlands Institute for Metals Research, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands Abstract The microstructure of a TiBRi composite coating, obtained by laser cladding a Ti-6Al-4V substrate with a Ti/TiB2 powder mixture, was scrutinized using transmission electron microscopy (TEM). TiB showed three different morphologies: fine needles (200 nm diameter, 15 pm length), plates (thickness 1 pn, short length 3 pm and long length 15 pn) and coarse needles (diameter 3 pn and length 50 pn). All TiB is composed of both the stable B27 and the metastable Bf crystal structures. Intimate mixing of B27 and Bf is possible because B27(200) planes fit excellently on BA110) or (1-10) planes (with B27[010]//B~001]) that easily leads to stacking disorder. Aspects of disorder are quantitatively analysed using high-res

Keywords