Precipitation Process in a Deformed NiTi Near Equiatomic Alloy

Abstract
The precipitation process in deformed NiTi alloys was studied in the work. The alloys had a nominal composition of 50.6 at.% and 51.0 at% of nickel. Specimens were deformed by 5 - 10 % and then aged at the temperature range 400 - 600°C. Electron microscopy studies showed that dislocations presence influence the precipitation process. This is especiaily visible in the Ni50.6%-Ti alloy were the particles nucleate at dislocations only. Ageing at 600°C causes healing out the dislocation and the precipitates do not occur in the alloy. Also in the alloy with larger content of nickel interaction between dislocations and precipitates is observed.