【摘要】 采用ＴＥＭ观察沿界断口萃取碳复型和金属薄膜．结果表明，固溶处理后，晶界表面Ｃ／Ｃｒ比较高（或较低）的区域存在Ｃｒ７Ｃ３（或Ｃｒ２３Ｃ６），炉冷时析出大尺寸的Ｃｒ７Ｃ３；７７５℃时效，ＴｉＣ退化成Ｃｒ２３Ｃ６，片状Ｃｒ７Ｃ３析出倾向较大；８５０℃时效，Ｃｒ２３Ｃ６密集分布，数量较多．铝含量较高时，晶内γ＇的沉淀倾向和长大速度较大；第三段时效热处理时γ＇有两种沉淀机制．更多还原

【Abstract】 Foils and extraction carbon replica from intergranular rupture specimens were studied by means of TEM. The results showed that Cr7C3/Cr23C6 existed at relatively high/low C/Cr ratio areas of grain boundaries after solution treatment,and large-sized Cr7C3 precipitated while furnace cooling. Aged at 775℃,TiC degenerated to Cr23C4 and Cr7C3 tended to precipitated in lamellar form, and the amount and density of Cr23C6 precipitation increased with age-temperature from 775℃ to 850 ℃. The high Al content increased the precipitation tendency and the growth rate of γ’ phases,and γ’ phases precipitated in two different ways in the third step aging treatments.更多还原