Modification of wear and fatigue characteristics of Ti-V-Al alloy by Cu and Ni ion implantation and high-current electron beam treatment

After Cu (60 keV, D = 2 x 10(17) cm(-2)) and Ni (40keV, D = 5 x D-16 cm(-2) ) ion implantation and subsequent high-current electron beam (HCEB) treatme nt, Ti-41 -V-41 -Al-18 alloy has been investigated. In addition to implante d Cu and Ni ions, high concentration of oxygen of about 14 at% and carbon o f about 15 at% were found in the layer of 60 nm. The surface alloy layer wa s composed of a number of structures: the grains of a dislocation substruct ure (2 x 10(10) cm(-2)), the grains with plates, and the grains with a pack ed martensite. The disorientation of regions was observed. The implanted al loy was found to have a decreased wear ability as well as an increased fati gue limit for cycling loads to 30%. After Cu, Ni implantation and HCEB trea tment this fatigue limit increased to 60%, the subsequent furnace annealing increasing it to 90%. Hardness also increased and the value of friction co efficient decreased by a factor of 1.8 after this double implantation and H CEB treatment. (C) 2001 Elsevier Science Ltd. All rights reserved.