摘要
为了深入认识新型奥氏体耐热钢Super304H(0.1C-18Cr-9Ni-3Cu-Nb,N)的微观组织,利用光学显微镜、扫描电子显微镜、电子探针和X射线衍射等手段,研究了Super304H钢合金元素的分布和析出相的组成及分布形态.试验结果表明,Super304H钢在供货状态下的显微组织由γ-基体和析出相组成.与传统的18-8不锈钢相比,这种奥氏体钢晶粒均匀细小,晶粒尺寸约46μm.析出相主要由Nb(C,N)和富铜相组成,Nb(C,N)有呈方向性分布的条块状和呈弥散分布的细小颗粒状两种形态,条块状的Nb(C,N)是软化过程中残留下来的,而弥散分布的是固溶处理及冷却过程中析出形成的.其中弥散分布的Nb(C,N)与富铜相对细化晶粒和改善钢的高温强度起重要作用,而多种复合强化机制使得Super304H钢具有优异的高温性能.
In order to understand the microstructure of novel austenitic heat-resistance steel Super304H （0. 1C-18Cr-9Ni-3Cu-Nb,N）,the composition and morphology of precipitated phases were investigated by the means of optical microscope,scanning electron microscopy （SEM）,electron probe microanalysis （EPMA） and X-ray diffraction （XRD）. Results show that the microstructure of Super304H under supply condition consists of γ-matrix and other precipitated phases. Compared with conventional 18-8 stainless steel,the grain of Super304H is finer and the mean grain size is about 46 μm. The precipitated phases mainly consist of Nb（C,N） and Cu-rich phase. The micro-morphology of Nb（C,N） includes two types,which are lath-shaped and fine particles with dispersive distribution. The lath-shaped Nb（C,N） is the remains of softening process, and dispersively distributed Nb（C,N） is formed during solution treatment and cooling process. The dispersively distributed Nb（C,N） and Cu-rich phase have an important role in the improvement of high-temperature properties,and the excellent high-temperature properties of Super304H are attributed to the multiple strengthening mechanisms.
出处
《材料科学与工艺》
EI
CAS
CSCD
北大核心
2010年第2期256-261,共6页
Materials Science and Technology
基金
山东省电力集团公司重点科技项目(2007A-47)
山东省自然科学基金资助项目(Z2006F07)
