Research on shape memory effect and corrosion resistance of the pipe joint of Fe-Mn-Si-Cr-Ni base shape memory alloy

Shape memory effect and corrosion resistance of the pipe joint of Fe-Mn-Si-Cr-Ni memory alloy were studied inthis paper.The results showed that with pre-deformation increasing,shape memory effect of the pipe joint would decline and the recovery of strain was on the rise.When the pre-deformation was more than 5.3%,the range of the rise was not significant.The connected pipe joint was more vulnerable to corrosion in a medium simulated oil field conditions than ina 3.5% NaCl solution.Compared to the unconnected pipe joint,corrosion resistance of the connected joint would decrease in the simulation media.It is due to the surface tensile stress caused by recovery stress and stress induced e martensite.Moreover,with pre-deformation increasing,corrosion resistance of the connected joint would decrease.It is the result of the combination of recovery stress,pipe joints crack and increase of crystal defect density.