Effects of annealing on structure,texture and mechanical properties of SP-700 alloy sheets
The effects of annealing temperature on the anisotropy of microstructure,texture and mechanical properties of SP-700 alloy sheet were studied using optical microscope(OM),electron backscatter diffraction(EBSD)and uniaxial tensile test.The results show that the grain equiaxed degree of the SP-700 alloy sheet increases with the increase of annealing temperature.The texture type of annealing at annealing temperature of 780℃is unchanged;when the annealing temperature is 860℃,the transformation of primary α to secondary α phase forms a new texture.After annealing at 900℃,the structure type changes to basket weave structure,and the texture type is pyramid texture and R-type texture.The pyramidal texture orientation of α phase is the reason for the anisotropy of mechanical properties of the original sheet.The hindrance of the intracrystalline substructure to the slip system at the initial stage of deformation affects the room temperature strength in different directions of the sheet.With the increase of annealing temperature,the elimination of intracrystalline substructure and the generation of new texture orientation lead to the enhancement of anisotropy of mechanical properties.Additionally,the differences in grain morphology and phase content can also lead to changes in anisotropy.The fracture mechanism of the original sheet is ductile fracture,and the fracture characteristics in different directions are slightly different.
NETL
NSTL
万方数据
维普
