Microstructural evolution analysis of grains and tensile properties of tin bronze in hot extrusion at different temperatures

摘要

In this paper, Electron Back-Scattered Diffraction is adopted to analyze the tin bronze microstructural changes of grains and grain boundaries in hot extrusion from 620 to 720 degrees C. The result shows that the size of grains grows as the temperature rises with a competitive status between recrystallisation and subgrains and deformed grains, and shows a random distribution with no obvious preferred orientation in structure. High angle grain boundaries (30 degrees) are most common with a large quantity of Sigma 3 boundaries at 60 degrees. Twin grains firstly appear in recrystallisation and grow continuously at subgrains. In the tensile test, re-crystallised grains had certain influence on the plasticity of tin bronze. Along with the elongation of tin bronze at temperatures above 700 degrees C, its plasticity also declined.