不同热处理状态下镍基耐蚀合金析出相的定性定量分析

发布时间：2018-04-16 06:09

  本文选题：镍基耐蚀合金 + 金属间相　； 参考：《冶金分析》2015年01期

【摘要】：镍基耐蚀钢的性能,在很大程度上取决于钢中各种相的数量、组成、大小、分布状况和合金元素在晶界的分配情况。镍基耐蚀钢经过等温热处理,通常会形成碳化物相、金属间相等析出相。这些析出相在合金中的形成将导致钢的脆化,显著降低钢的塑性、韧性和耐蚀性。为了对不同热处理条件下镍基耐蚀合金析出相做定性定量分析,实验在选择好合适的电解制度后,利用电解分离方法将析出相从基体中分离。通过扫描电镜(SEM)和X射线衍射(XRD)定性研究了提取后析出相的形貌以及结构特性的变化过程;并利用Rietveld全谱拟合法计算不同析出相的组成及含量,最后还讨论了析出相含量与材料耐蚀性能间的关系。实验结果表明900℃时效形成的析出相最多,且析出相的含量随时间的延长呈明显上升的趋势;腐蚀性能评价结果表明析出相的含量与平均腐蚀速率存在一定的正相关,即随着析出相含量的增加,材料的平均腐蚀速率也增加,耐蚀性能减弱。
[Abstract]:The properties of Ni-based corrosion resistant steels depend to a great extent on the amount, composition, size, distribution and distribution of various phases in the steel and the distribution of alloying elements at grain boundaries.After isothermal heat treatment, Ni-based corrosion resistant steel usually forms carbide phase, which is the same precipitated phase between metals.The formation of these precipitated phases in the alloy will lead to the embrittlement of the steel, which will significantly reduce the plasticity, toughness and corrosion resistance of the steel.In order to qualitatively and quantitatively analyze the precipitated phase of Ni-base corrosion resistant alloy under different heat treatment conditions, the precipitation phase was separated from the matrix by electrolytic separation method after the proper electrolysis system was selected in the experiment.The morphology and structural characteristics of the precipitated phases after extraction were qualitatively studied by means of scanning electron microscopy (SEM) and X-ray diffraction (XRD), and the composition and content of different precipitates were calculated by Rietveld full-spectrum fitting method.Finally, the relationship between the content of precipitated phase and the corrosion resistance of the material is discussed.The experimental results show that the precipitation phase formed at 900 鈩，

本文编号：1757603