Title :
Surface hardening of NiTi shape memory alloy induced by surface nanocrystallization via surface mechanical attrition treatment
Author :
Hu, Tao ; Chu, C.L. ; Lu, J. ; Chu, Paul K.
Author_Institution :
Dept. of Phys. & Mater. Sci., City Univ. of Hong Kong, Kowloon, China
Abstract :
In terms of grain refinement mechanism induced by plastic deformation, NiTi shape memory alloy (SMA) was processed by means of surface mechanical attrition treatment (SMAT) in order to achieve surface nanocrystallization for surface hardening. The cross sectional microhardness of the SMAT treated NiTi SMAs was measured, in comparison with those of the residual stress relaxation and recrystallization annealled NiTi specimen. The results show that surface nanocrystallization induced by grain refinement enhanced the surface hardness of NiTi SMAs.
Keywords :
annealing; crystallisation; grain refinement; internal stresses; microhardness; nickel alloys; plastic deformation; shape memory effects; stress relaxation; surface hardening; titanium alloys; NiTi; cross sectional microhardness; grain refinement mechanism; plastic deformation; recrystallization annealled specimen; residual stress relaxation; shape memory alloy; surface hardening; surface hardness; surface mechanical attrition treatment; surface nanocrystallization; Annealing; Biomedical measurements; Immune system; Materials science and technology; Optical microscopy; Refining; Residual stresses; Shape memory alloys; Surface resistance; Surface treatment;
Conference_Titel :
Nanoelectronics Conference (INEC), 2010 3rd International
Conference_Location :
Hong Kong
Print_ISBN :
978-1-4244-3543-2
Electronic_ISBN :
978-1-4244-3544-9
DOI :
10.1109/INEC.2010.5425171
