Low temperature anomalies of physico-mechanical characteristics of pseudoamorhous nikelid-titanium

The structure, mechanical properties and electroresistance of crystalline and pseudoamorphous (prepared by rolling at 300 K by 50 and 90 %) nikelid-titanium both in the initial state and after annealing at temperatures ranged from 513 to 873 K have been investigated. It is found that the electroresistance of pseudoamorphous Ti-Ni exceeds 200 μ Ohm centre dot cm , monotonously decreases with increasing annealing temperature and has a minimum (Tmin approx 17-19 K) in a low temperature region 4,2-50 K. A nonmonotonous temperature dependence of tensile strength is observed in a temperature range of 4,2 to 20 K. It increases with the degree of strain by rolling of the material studied. The results obtained are analyzed. It is supposed that the anomalies in the temperature dependences of tensile strength and electroresistance are associated with the low temperature polymorphism of pseudoamorphous Ti-Ni in a temperature range 10-20 K