【摘要】：利用光學(xué)顯微鏡、掃描電鏡及透射電鏡,結(jié)合Thermo-Calc熱力學(xué)分析,研究了鈮穩(wěn)定化0Cr19Ni15Mn5Mo2NbN奧氏體不銹鋼鑄鋼晶界處高溫相析出行為及其對(duì)力學(xué)性能的影響。結(jié)果表明,0Cr19Ni15Mn5Mo2NbN鋼晶界處存在Nb Cr(CN)、Nb(CN)2種大尺寸高溫析出相,均為凝固末期液析形成。在鈮含量確定條件下,這2種大尺寸晶界析出相在凝固末期的競(jìng)爭(zhēng)析出行為受碳含量的影響。碳含量存在臨界成分,碳含量低于臨界成分時(shí),Nb Cr(CN)首先液析形成;碳含量高于臨界成分時(shí),Nb(CN)首先液析形成。液析形成的NbCr(CN)熱穩(wěn)定性較高,1 050℃固溶處理無(wú)法使之完全溶入奧氏體。沿晶界分布的大尺寸析出相,對(duì)0Cr19Ni15Mn5Mo2NbN鑄鋼固溶熱處理后的塑性及沖擊韌性損害較大。
[Abstract]:The precipitation behavior of high temperature phase at grain boundary of niobium stabilized 0Cr19Ni15Mn5Mo2NbN austenitic stainless steel and its effect on mechanical properties were studied by means of optical microscope, scanning electron microscope and transmission electron microscope, combined with Thermo-Calc thermodynamic analysis. The results show that there are two kinds of large size high temperature precipitated phases of Nb Cr (CN), Nb (CN) at grain boundary of 0Cr19Ni15Mn5Mo2NbN steel, all of which are formed by liquid precipitation at the end of solidification. The competitive precipitation behavior of these two large grain boundary precipitates at the end of solidification is affected by the carbon content under the condition of the determination of niobium content. When the carbon content is lower than the critical composition, Nb Cr (CN) is firstly formed by liquidation, and when the carbon content is higher than the critical composition, Nb (CN) is formed first. The NbCr (CN) formed by liquid precipitation has high thermal stability and can not be completely dissolved into austenite by solution treatment at 1 050 鈩，

本文編號(hào)：2416314