Patent Document ID: 4435229
Application ID: 06308127
Patent Flag: 1

Claim One:
1. A method of training a shape memory alloy so that the alloy has a two-way shape memory when the alloy is operated in a working cycle for converting heat into mechanical work with the conditions of the cycle including an upper operating temperature T of the alloy and a stress .sigma..sub.w at which the alloy is operated in the working cycle, the method comprising iteratively performing the steps of heating the alloy under a first training stress .sigma..sub.1 to a temperature T.sub.H which is above said temperature T, cooling the alloy to a temperature T.sub.C which is below the zero-force transition temperature of the alloy, deforming the alloy at T.sub.C while applying to the alloy a second training stress .sigma..sub.2 where .sigma..sub.2 .noteq..sigma..sub.1 and .sigma..sub.2 .gtoreq..sigma..sub.w, heating the alloy back to T.sub.H, and changing stress on the alloy to the first training stress.