Objective Over certain composition ranges titanium alloys form orthorhombic martensites on quenching from the beta phase field. Subsequently, the martensite decomposed in tempering spinodal decomposition has been shown to be responsible in some instances. Theoretical crystallographic modelling work suggests that the observation of orthorhombic symmetry in the martensite may be a consequence of initial spinodal decomposition rather than a necessary precursor to it. This project aims to elucidate the mechanism of formation of the orthorhombic martensite and its relationship to spinodal decomposition on tempering by a study of a range of model binary titanium alloys. The influence of the transformations on the mechanical properties developed will also be studied in view of reported problems of hardening and embrittlement in heat-affected zones of titanium alloy welds attributed to tempered orthorhombic martensite structures. The work to be carried out in Ukraine consists of three parts: calculation of crystallographic parameters for martensite transformation in a number of titanium alloys covering the orthorhombic/spinodal range; x-ray diffraction studies to correlate measurements with theoretical prediction; and low-angle x-ray diffraction to study the evolution of the spinodal decomposition products. Imperial College has responsibilities for transmitting electron microscopy studies of samples from the Ukrainian work to study directly microstructural evolution via the martensitic and spinodal reactions and for measurement of the associated mechanical properties. Programme(s) IC-INTAS - International Association for the promotion of cooperation with scientists from the independent states of the former Soviet Union (INTAS), 1993- Topic(s) 62 - New Materials Call for proposal Data not available Funding Scheme Data not available Coordinator IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY AND MEDICINE EU contribution No data Address Royal School of Mines, Prince Consort Road SW7 2BP LONDON United Kingdom See on map Total cost No data Participants (2) Sort alphabetically Sort by EU Contribution Expand all Collapse all National Academy of Sciences of Ukraine Ukraine EU contribution No data Address 252142 Kiev See on map Total cost No data Technische Universität Hamburg-Harburg Germany EU contribution No data Address 21071 Hamburg See on map Total cost No data