摘要
采用雾化?热挤压工艺制备Fe13CrWTiY高温合金,通过显微观测和XRD分析研究750～1 250℃温度范围内真空退火后的合金显微硬度与组织结构变化。结果表明,该合金在1 100℃以上的高温下退火后,显微硬度急剧上升。退火温度达到1 250℃时组织结构出现显著的等轴化和粗化,并发生α→γ相变;在高温下可能有铁铬金属间化合物相σ析出,这种高硬度的析出相使合金硬度增大,而新相的生成会消耗基体中的大量Cr元素,使Cr含量降低,从而使α→γ相变成为可能。
Fe-based superalloy Fel3CrWTiY was prepared via hot-extrusion method using atomized powder as raw material, and the change of microhardness and microstructure of the superalloy at 750~ 1 250 ℃ were investigated. A abnormal hardening behaviour after the high temperature （above 1 100℃） annealing was found which is interpreted on the basis of information derived from microstructural studies and XRD results. And a α→γ transformation has found in case of the annealing temperature raised to 1 250℃, which is suggested, therefore, that an intermetallic consisting of Fe and Cr, the σ phase, precipitated in this situation. The high hardness of precipitated phase could enhance the whole hardness of the alloy, and the precipitation of the σ phase with a high content of Cr could reduce the Cr content of matrix and therefore make the transformation possible.
出处
《粉末冶金材料科学与工程》
EI
2008年第4期245-248,共4页
Materials Science and Engineering of Powder Metallurgy
基金
国家自然科学重点基金资助项目(50634060)
面上基金资助项目(50704037)
关键词
铁基高温合金
显微硬度
退火
相变
Fe-based superalloy
mierohardness
annealing
phase transformation
