Journal of Materials Science, Vol.30, No.6, 1577-1583, 1995
A Study on Martensitic-Transformation in Ti-50-X/2Ni50-X/2Cux Alloys with X-Less-Than-or-Equal-to-10 at Percent
The effect of Cu additions on the martensitic transformation sequence and temperature in Ti50-x/2Ni50-x/2Cux alloys with x : 1-10 at% are investigated by ER, DSC, X-ray and IF measurements. Experimental results show that the transformation sequence of Ti50-x/2Ni50-x/2Cux alloys with x : 1-4 at% proceeding as two-stage 82 --> R --> B19’ transformation on cooling and Ti50-x/2Ni50-x/2Cux alloys with x = 5, 10 at% have no martensitic transformation. The addition of Cu in Ti-50-x/2 Ni50-x/2Cux alloys assists the formation of R-phase, a behaviour which is quite different from that in Ti50Ni50-xCux alloys. Both the Ms and T-R temperatures decrease rapidly with increasing Cu addition in Ti50-x/2Ni50-x/2Cux alloys with x:1-4 at%. It is proposed that the Cu + Ni effects on the Ms temperature in Ti50-x/2Ni50-x/2Cux alloys is similar as Cu + Ni effects in Ti50Ni50-xCux alloys and as Ni effects in as-quenched Ni-rich TiNi alloys.
Keywords:SHAPE MEMORY CHARACTERISTICS;AGED TI49NI51 ALLOY;NI-CU ALLOYS;INTERNAL-FRICTION;SHEAR MODULUS;DEFORMATION;TI50NI47FE3;BEHAVIOR;PHASE