Microstructures and mechanical properties of nanocrystalline NiTi intermetallics formed by mechanosynthesis  

作　　者：S.Arunkumar P.Kumaravel C.Velmurugan V.Senthilkumar 

机构地区：[1]Vinayaka Mission's Kimpananda Variyar Engineering College,Salem 636308,Tamilnadu,India [2]Institute of Road and Transport Technology,Erode 638316,Tamilnadu,India [3]National Institute of Technology,Trichy 620015,Tamilnadu,India

出　　处：《International Journal of Minerals,Metallurgy and Materials》2018年第1期80-87,共8页矿物冶金与材料学报（英文版）

摘　　要：The formulation of nanocrystallinc NiTi shape memory alloys has potential effects in mechanical stimulation and medical im- plantology. The present work elucidates the effect of milling time on the product＇s structural characteristics, chemical composition, and mi- crohardness for NiTi synthesized by mechanical alloying for different milling durations. Increasing the milling duration led to the formation of a nanocrystalline NiTi intermetallic at a higher level. The formation of nanocrystalline materials was directed through cold fusion, fractur- ing, and the development of a steady state, which were influenced by the accumulation of strain energy. In the morphological study, uninter- rupted cold diffusion and fracturing were visualized using transmission electron microscopy. Particle size analysis revealed that the mean particle size was reduced to -93 μm after 20 h of milling. The mechanical strength was enhanced by the formation of a nanocrystalline in- termetallic phase at longer milling time, which was confirmed by the results of Vickers hardness analyses.The formulation of nanocrystallinc NiTi shape memory alloys has potential effects in mechanical stimulation and medical im- plantology. The present work elucidates the effect of milling time on the product＇s structural characteristics, chemical composition, and mi- crohardness for NiTi synthesized by mechanical alloying for different milling durations. Increasing the milling duration led to the formation of a nanocrystalline NiTi intermetallic at a higher level. The formation of nanocrystalline materials was directed through cold fusion, fractur- ing, and the development of a steady state, which were influenced by the accumulation of strain energy. In the morphological study, uninter- rupted cold diffusion and fracturing were visualized using transmission electron microscopy. Particle size analysis revealed that the mean particle size was reduced to -93 μm after 20 h of milling. The mechanical strength was enhanced by the formation of a nanocrystalline in- termetallic phase at longer milling time, which was confirmed by the results of Vickers hardness analyses.

关 键 词：nickel-titanium shape memory alloy lattice strain NANO-CRYSTALLINE mechanical alloying microstructural characterization 

分 类 号：TF0[冶金工程—冶金物理化学]