| 摘要 |
The invention relates to a Fe-Mn-Si-Cr-Ni shape memory alloy used for pipe couplings or actuators. The claimed alloy has the following chemical composition expressed as mass percentage : 13...25% Mn, 2.5...4% Si, 3...4% Cr, 1.5...2% Ni, 0.1...0.6 % C, 0.2...1% Cu, 0.05...0.2% Nb, 0.05...0.1% Ti, 0.05...0.1% V, maximum 0.3% impurities, and Fe for the remainder, the sum of the concentration of the elements Mn, Si, Cr, Ni and C of a value X = % Mn + % Si + % Cr + % Ni +C = 18...28 and the % Cr/ % Ni ratio = 2. The claimed process consists in smelting the components in an induction furnace in a neutral crucible based on aluminium trioxide, pouring the smelting into metal moulds protected with refractory paint, ensuring a maximal cooling rate of 50° C/min, homogenizing annealing at a temperature of 1100°C, water hardening at 1000°C, and finally subjecting it to plastic deformation by rolling at a temperature of 1000°C with a degree of reduction of 15% to a thickness of minimum 0.25 mm, the hot mould resulting from the hot plastic deformation process or being imprinted by maintaining it in constricted condition at a temperature of 900°C. |
