Influence of α/β interface phase on the tensile properties of laser cladding deposited Ti-6Al-4V titanium alloy

• 来源期刊: 材料科学技术（英文版）
• 年，卷（期）: 2017,（7）
• 页码范围: 675-681
• 页数: 7页
• 语种: 英文

摘要

Laser cladding deposited Ti-6Al-4V titanium alloy universally shows more complex microstructures,each of which has significant effect on mechanical properties.Of particular α/β interface phase has been observed in this paper under certain conditions.It demonstrates that the influence of the α/β interface phase on the tensile properties is closely associated with dislocations and twin substructure through comparison experiments.The results show that the α/β interface phase hinders dislocation motion and decreases effective slip length.In addition,the twin substructure has been activated in the α/β interface phase during tensile process and has acted somehow like grain boundaries.Therefore,the strength and the work-hardening rate of the laser cladding deposited Ti-6Al-4V titanium alloy have been significantly improved due to the dynamic Hall-Petch effect.Besides,the α/β interface phase leads to more uniform dislocations distribution,which implies that relative lower local concentrated stress will be produced along the α/β interface phase or colony boundary after the same amount of plastic deformation.Moreover,the twinning-induced plasticity effects in the α/β interface phase further increase the plastic deformation capacity.These results in higher elongation for the laser cladding deposited Ti-6Al-4V titanium alloy.It can be concluded that the current work suggests an effective method to simultaneously improve the strength and plasticity of laser cladding deposited Ti-6Al-4V titanium alloy based on the α/β interface phase.