The Transformation In Cu-Zn-Al Shape Memory Alloy

Cu-Zn-Al shape memory alloy is a kind of function material with fine performance and low cost. The alloy with the composition of Cu-Zn26-Al4 quenched at high temperature directly has fine shape memory effect and its shape memory effect is better than other alloy with similar composition. The microstructure is pick-like martensite. After training, the alloy can gain stable two-way shape memory effect, the descend of SME is little and the training efficiency is high. Under alternating stress, the two-way shape memory effect is heavily destroyed. Aging at room temperature, there is no stability of martensite. The alloy has utility value.There is an unknown transformation process in Cu-Zn-Al alloy named quasi-fluid transformation. Quasi-fluid cells' crystal lattice and phase will change when transformation happen. The change of temperature or stress and the load of electric field or magnetic field will induce this kind of transformation. The obvious change of height in X-ray diffraction pattern proved the happen of transformation. Sampling on the gray of cells at different moment and using phase randomization theory can prove the existence of chaos movement. Using Schlogl model and non-linear dynamic equation, we can prove theoretically that this kind of transformation is a self-organization phenomenon caused by the change of environment at critical point.