The effect of niobium element on the tensile behavior in GH3535 alloy at room temperature and 750 °C

The microstructure and tensile behavior of GH3535 and 2 wt% niobium (Nb) modified GH3535 alloys at room temperature (RT) and 750 degrees C were systematically investigated. It is found that Nb element is distributed in both matrix and M6C carbide, while the type and content of carbide in GH3535 alloy are barely affected by Nb element. The tensile properties at RT and 750 degrees C are improved by adding Nb element, which can be ascribed to the synergistic effect of the solid solution strengthening, and nano twins strengthening. Additionally, they will be improved by grain refinement at RT. The strengths of both alloys at 750 degrees C are lower than that of RT, which is related to the softening caused by dislocations climbing and softening of grain boundaries at high temperature.

Automated summary

The microstructure and tensile behavior of GH3535 and GH3535 alloys modified with 2 wt% niobium (Nb) were investigated at room temperature and 750 degrees Celsius. The addition of Nb element improved the tensile properties, attributed to the synergistic effect of solid solution strengthening and nano twins strengthening. Furthermore, grain refinement also played a role in enhancing the tensile properties at room temperature. However, the strengths of both alloys at 750 degrees Celsius were lower due to the softening caused by dislocations climbing and softening of grain boundaries at high temperature.