The effects of preparation and crystal growth methods on the microstructure, composition, and oxidation of CoTi(Zr)intermetallics were dealt with . A group of methods has been used to produce CoTi and CoTi(Zr) crystals to preventthe formation of titanium oxide particles during melting and crystal growth. The results show that more oxidesformed when using powdered starting materials even though the metals handled were and melted under an inert gasatmosphere; using bulk starting materials produced alloys showed less oxidation than powders, but adding a smallamount of Al to getter the oxygen was not sufficient to prevent TiO2 formation. However, using a slightly reducingatmosphere during initial melting was highly effective in reducing the formation of oxide. Crystal growth carried outin Ar did not reduce the amount of oxide but only redistributed the particles. TiO2 particles were found only inthe grain boundaries after crystal growing, where they obstructed grain growth. Crystal growth in a vacuum wasfound to be essential in producing oxide free crystals. A seed selection technique was developed and used in growingCoTi single crystals. The microstructures of the samples were determined using optical microscopy, scanning electronmicroscopy and transmission electron microscopy, including the morphologies, grain sizes, oxide distributions andcrystal structure confirmation.
