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0Cr17Mn14Mo2N不锈钢在1050—1350℃固溶处理后,具有γ+δ复相组织。金相定量测定了固溶温度下δ铁素体的含量,并用电子探针及电解分离化学分析方法,分别测定了合金元素在γ及δ相间的分配,随固溶温度由1050℃升至1350℃,δ铁素体含量由23％增至42％,合金元素(铬、锰、钼)在γ及δ两相间的浓度渐趋均匀,对固溶处理后,在550—950℃温度范围等温加热时,δ铁素体的分解过程进行了金相研究和磁性测量,发现δ铁素体可以有下列几种转变:δ→γ′,δ→κ(χ)+γ′和δ→δ′+κ(χ)。其转变产物有γ′奥氏体,Cr_2(CN),(CrFe)_7C_3,Cr_(23)C_6,χ及σ相。转变的类型和转变产物随固溶及等温加热温度的不同而有所改变。钢中大量锰(～14％)的存在加速了χ相的生成并扩大了χ相的形成温度范围。χ相形成过程中伴随着硬度增高以及冲击韧性明显下降。测得χ相的平均化学式为Fe_(31)Cr_(14)Mn_(8.5)Mo_(4.5),点阵常数α_0~(552)=8.86埃。 δ铁素体恒温转变动力学曲线具有“C”曲线形式,转变有孕育期。δ→κ(χ)+γ′共析转变在850℃最快。

δ-ferrite in 0Cr17Mn14Mo2N stainless steel formed at 1050—1350℃ was measured quantitatively by metallographic methods, and the distribution of alloy elements between δ-ferrite and austenite was determined by electron-probe and electrolytic extraction phase analysis. It was found that the amount of δ-ferrite increases from 23% at 1050℃ to 42% at 1350℃. As to be expected, the concentration difference of Cr, Mn, Mo between δ-ferrite and austenite became increasingly smaller as the solution temperature was increased.After reheating in the range of 550—950℃, several types of transformation in δ ferrite including δ→γ′, δ→κ(χ)+γ′ and δ→δ′+κ(χ) may take place, and phases like Cr_2(CN), (CrFe)_7C_3, Cr_(23)C_6, χ and σ were found to appear. Both the type and product of transformation varied with the temperature of solution treatment and the subsequent isothermal heating. The high Mn content (14%) in steel promoted the formation of χ-phase expressed as Fe_(31)Cr_(14)Mn_(8.5)Mo_(4.5), and its cell constant was α_0~(552)=8.86(?).The kinetics of isothermal transformation in δ ferrite is of the C-curve type with its nose for δ→κ(χ)+γ′ at 850℃.