Properties and microstructure of Ti6Al4V by deformation accelerated low temperature plasma nitriding

An integrated low-temperature nitriding process was carried out for Ti6Al4V to investigate its effect on microstructure and properties. The process was designed to enhance the nitriding kinetics in low-temperature (500 °C) nitriding by deformation, and to strengthen Ti6Al4V alloy by dispersion at the same time. Specimens of Ti6Al4V alloy were treated through the process of solid solution strengthening-cold deformation-nitriding at 500 °C. The white nitriding layer is formed after some time and then kept stable, changing little with the deformation degree and time. The effect of aging on substrate is significant. Surface hardness and substrate hardness increase with deformation increasing. The construction was investigated by XRD. The surface nitrides are TiN, Ti2N, Ti4N3-X and Ti3N1.29, and the nitrides in cross-section are Ti3N1.29 and TiN0.3. The wear tests of specimens after nitriding, aging and deformation were carried out, and the test data show that the nitrided pieces have the best wear resistance.