Effect of Thermomechanical Cyclic Loading Condition on Two-Way Strain in Ti-Ni-Cu Shape Memory Alloy

Y. Takeda, T. Yamamoto, A. Goto, T. Sakuma
2008 Transactions of the Materials Research Society of Japan  
This study describes the effect of thermomechanical cyclic condition on two-way strain in Ti-Ni-Cu shape memory alloy. The material used in this study is Ti-41.7Ni-8.5Cu(at%) shape memory alloy. The specimen shape is a wire with lmm diameter and 70 mm gage length. The specimen was heat treated at 623K for 3.6ks. The process of the cyclic loading test in this study is loading-unloading-heating-unloading-cooling cycle. The specimen was loaded to given applied strain and subsequently unloaded. And
more » ... ently unloaded. And then, the specimen was heated up to 373K or 423K and was kept at the temperature for 0.6ks under the constrained strain condition followed by unloading and cooling under free strain condition. Also, the number of cycles is 30 cycles. This study discussed the effects of heating temperature, applied strain and number of cycles on two-way strain in Ti-41.7Ni-8.5Cu(at%) shape memory alloy. The two-way strain slightly increases with increasing heating temperature. An increase in the maximum applied strain up to 7.5% increases the two-way strain. There is hardly effect of the number of cycles on the two-way strain.
doi:10.14723/tmrsj.33.869 fatcat:hbdvqfyhhrdmvo5g3ynjj3iwxi