In this paper the effect of solution treatment on the corrosion resistance of welding joint of Ni56Cr22Mo13 alloy was studied by polarization curves, mass loss method, SEM. The results indicated that the composition of alloy welded was not uniform and the corrosion resistance of welding joint of Ni56Cr22Mo13 alloy was poor. After solution treatment, the corrosion resistance was enhanced.

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A beta phase containing titanium aluminum compound was prepared. Isothermal Fatigue(IF) were subjected at 650 °C at three strain rates, such as 6.67×10-3s-1, 6.67×10-4s-1, 6.67×10-5s-1to determine the effect of strain rate on cyclic stress-strain response (CSSR) of TiAl alloy during IF tests. The curves of cyclic stress-strain response were discussed and dislocations configuration were also observed by TEM. The results show that strain rates have an apparent effect on CSSR of TiAl alloy during IF tests and CSSR was identified that it had a close relationship with dislocation configuration and deformation twin.

Isothermal fatigue (IF) tests were carried out on the gamma-TiAl alloy in the temperature of 500°C, 650°C and 800°C under mechanical strain control in order to evaluate its cyclic deformation behaviors at elevated temperature. Cyclic deformation curves, stress-strain hysteresis loops under different temperature-strain cycles were analyzed and dislocations configurations were also observed by TEM. The mechanism of cyclic hardening or softening during IF tests was also discussed. Results show that during the IF tests, The hysteresis loops were almost symmetrical above 600 °C, such as 650 °C and 800 °C; The hysteresis loops at the temperature of 500 °C generated two apparent asymmetry, one was zero asymmetry, the other was tensile and compressive asymmetry; Dislocation configuration and slip behaviors are contributed to cyclic hardening or cyclic softening.