Phase transitions and thermal expansion in Ni 51– x Mn 36 + x Sn 13 alloys

Thermal expansion and structural and magnetic phase transitions in alloys of the Ni–Mn–Sn system have been investigated. The spontaneous martensitic transformation in Ni51–xMn36 + xSn13 (0 ≤ x ≤ 3) alloys is found to be accompanied by high jumps in the temperature dependences of the linear thermal expansion. The relative change in the linear sizes of these alloys at the martensitic transformation is ~1.5 × 10–3. There are no anomalies in the magnetic-ordering temperature range in the temperature dependences of the coefficient of linear thermal expansion. The differences in the behavior of linear thermal expansion at the martensitic transformation in Ni51–xMn36 + xSn13 (0 ≤ x ≤ 3) and Ni47Mn40Sn13(x = 4) alloys have been established.