Precipitation phenomena in Type 316L and 304L stainless steels were studied mainly by transmission electron microscopic (TEM) observations after cold-rolling ranging from 0% (as solution annealed) to 80% reduction in ...Precipitation phenomena in Type 316L and 304L stainless steels were studied mainly by transmission electron microscopic (TEM) observations after cold-rolling ranging from 0% (as solution annealed) to 80% reduction in thickness, and then by sensitization treatment. Precipitates were identified by electron diffraction analysis and EDS analysis. Precipitates observed in sensitized 316L stainless steel were sigma and chi phases, whereas carbide and sigma were observed in sensitized 304L stainless steel. Recrystallized grains were formed in 30% cold-rolled and sensitized 304L. However, the tendency toward recrystallization in sensitized 316L was much lower than in 304L. Precipitation of sigma and chi phases was accelerated by cold-rolling and they were observed at grain boundaries in lower cold-rolling; they were also seen, in grain interiors in higher cold-rolling. Higher deformation induced partially recrystallization combined with precipitation, resulting in the formation of heterogeneous microstructures.展开更多
The creep behaviors of the Ni added Ir 85 Nb 15 alloys were investigated at 1?650～1?800?℃ by compression tests in vacuum. X ray diffractometry, transmission electron microscopy and scanning electron microscopy were ...The creep behaviors of the Ni added Ir 85 Nb 15 alloys were investigated at 1?650～1?800?℃ by compression tests in vacuum. X ray diffractometry, transmission electron microscopy and scanning electron microscopy were conducted to characterize the microstructure and lattice misfit change by the addition of Ni in the Ir 85 Nb 15 alloy. The results reveal that the Ni addition has a significant effect on the creep resistance of the Ir 85 Nb 15 two phase refractory superalloys. Basing on the results, the relationship among the Ni addition, lattice misfit, microstructure development, and the creep behavior in the Ni added Ir 85 Nb 15 alloys is discussed.展开更多
文摘Precipitation phenomena in Type 316L and 304L stainless steels were studied mainly by transmission electron microscopic (TEM) observations after cold-rolling ranging from 0% (as solution annealed) to 80% reduction in thickness, and then by sensitization treatment. Precipitates were identified by electron diffraction analysis and EDS analysis. Precipitates observed in sensitized 316L stainless steel were sigma and chi phases, whereas carbide and sigma were observed in sensitized 304L stainless steel. Recrystallized grains were formed in 30% cold-rolled and sensitized 304L. However, the tendency toward recrystallization in sensitized 316L was much lower than in 304L. Precipitation of sigma and chi phases was accelerated by cold-rolling and they were observed at grain boundaries in lower cold-rolling; they were also seen, in grain interiors in higher cold-rolling. Higher deformation induced partially recrystallization combined with precipitation, resulting in the formation of heterogeneous microstructures.
文摘The creep behaviors of the Ni added Ir 85 Nb 15 alloys were investigated at 1?650～1?800?℃ by compression tests in vacuum. X ray diffractometry, transmission electron microscopy and scanning electron microscopy were conducted to characterize the microstructure and lattice misfit change by the addition of Ni in the Ir 85 Nb 15 alloy. The results reveal that the Ni addition has a significant effect on the creep resistance of the Ir 85 Nb 15 two phase refractory superalloys. Basing on the results, the relationship among the Ni addition, lattice misfit, microstructure development, and the creep behavior in the Ni added Ir 85 Nb 15 alloys is discussed.
