Microstructure analysis of stress rupture performance of Hastelloy C-276 alloy at 650C

作者：Ma Yan^*; Lu Daogang; Mao Xueping; Zhang Liyin; Cai Jun

来源：Rare Metal Materials and Engineering, 2010, 39(9): 1571-1574.

• Annealing twins
• Before and after
• Deformation twin
• Fracture surfaces
• Hastelloy C-276
• Hastelloy C-276 alloy
• High temperature
• High temperature stress
• Intergranular fracture
• Microstructure analysis
• Precipitation strengthening
• SEM and TEM
• Stress rupture

The microstructure of solid solution strengthened Hastelloy C-276 alloys before and after ruptured at 650°C under different tensile stresses was studied by SEM and TEM. The results show that the fracture surface displays typical dimple morphology, with a few intergranular fractures. It can be concluded that the C-276 alloy has very good high-temperature toughness. A few annealing twins and plenty of dislocations exist in the initial microstructure of C-276 alloy. And after persistent tensile experiments, a large number of deformation twins are formed in C-276 crystals. Moreover, many fine and dispersive precipitations are also formed in the grain boundary and intragranular. Therefore, a good high temperature stress rupture performance of the Hastelloy C-276 alloy arises from co-effects of solid solution-strengthening, precipitation- strengthening and possible deformation twin-strengthening.

• 出版日期2010
• 单位华北电力大学