| TiNiFe can be used in the high stress and pressure only if their strengthens are increased, so how to increase the strength of TiNiFe alloys or developing new alloys ,which possess low martensite transformation temperature and high strengthen, will be a aspect of high practicality.In this paper , TiNiFeMo alloys were studied concerning its corrosion , phase transformation characteristics, Shape memory effect. The optical microscope, SEM, XRD and Resistance Testing System at low temperature were used to test microstructure and phase transformation process. Corrosion properties of TiNi , TiNiFe and TiNiFeMo were investigated by means of Dipping and electrochemistry。It can be known that Mo has been melt in TiNiFe by means of SEM .The phase transformation process of B2 → R→ B19'happened in TiNiFeMo alloy in cooling ,reversed in heating.TiNiFeMo SMA wires were investigated in this paper.the results of experiment showed that,different annealing temperature have effects on R phase transformation with small lag. will have a tendency of decrease with the increase of temperature that is between 350℃ and 650 ℃ .then increase until750 ℃ .R phase transformation with small lag ,which make it be used as sensor or sensor wire in composite material.R phase transformation have a little tendency of decrease with the number of cycling,which proved that the stability of R phasetransformation .The corrosion ratio of TiNiFeMo is 1. 857 e-4 mm .a-1 。 corrosion is entireness. Curves of anode polarization were obtained . corrosion propertie of TiNiFeMo is better than TiNi ,TiNiFe. strees corrosion of TiNiFe couplings was studied , no cracks were found ,the result show s that TiNiFe couplings can meet the commands for using.Two way SME of wire and spring can be obtained by thermal mechanical cycling .spring was training 20 times in the liquid nitrogen at martansist state,the recover ratio is 13.3%.
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