PM法制备9Cr-ODSRAFM钢的组织性能研究

发布时间：2018-06-17 23:41

  本文选题：9Cr-ODS + RAFM钢　； 参考：《华中科技大学》2011年硕士论文

【摘要】：本文首先简单介绍了核聚变的发展及其优点,综述了第一壁结构材料的运行环境及其国内外研究现状。基于此,本论文采用粉末冶金(Powder Metallurgic,PM)法制备9Cr-ODS RAFM钢,将设计好成分的原始粉末进行机械合金化(Mechanical Alloying,简称MA)、氢气气氛退火、模压成型和真空烧结。分析了MA工艺参数对合金化效果的影响及原因,研究了烧结温度对烧结体组织及性能的影响,并通过氧化实验研究合金的高温抗氧化性能。 研究了不同MA因素对9Cr-ODS RAFM钢粉末合金化效果的影响,主要包括对球磨时间、球料比(Ball to Powder Weight Ratio,BPR)及过程控制剂(Process Control Agent,PCA)的研究。采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)对球磨后粉末进行物相分析及形貌观察。结果表明:BPR及球磨转速一定时,随着球磨时间的延长,合金程度提高;球磨时间一定,BPR越大越有利于合金化;PCA的添加有利于提高出粉率、减弱冷焊现象降低粉末硬度。 探索了烧结温度对合金致密化及性能的影响。运用光学显微镜(OM)、能谱分析仪(EDS)、拉伸试验机等仪器,分析测试烧结体的显微组织及微区成分,并测试材料的抗拉强度。结果表明:烧结试样的相对密度、抗拉强度随着烧结温度的提高逐渐增大,当烧结温度为1390℃时,二者的值分别为95.4%,562.9MPa,为最佳烧结温度。本文还研究了Si的添加和热等静压(HIP)工艺对烧结体性能影响。HIP可以大大提高合金的抗拉强度(最高达875MPa),添加Si有利于合金的致密化,提高材料的抗拉强度。 将在不同温度下烧结的合金于750℃下恒温氧化95h,分析其氧化动力学曲线,观察氧化膜的厚度变化及完整性,并对氧化膜成分进行EDS分析。研究表明相同时间氧化后低温烧结试样的氧化增重快,氧化速率常数大,氧化膜较厚,且缺陷较多。
[Abstract]:In this paper, the development and advantages of nuclear fusion are briefly introduced, and the operating environment of the first wall structure material and its research status at home and abroad are summarized. Based on this, 9Cr-ODS RAFM steel was prepared by powder metallurgy (PM) method. Mechanical alloying (MA), hydrogen atmosphere annealing, moulding and vacuum sintering were carried out. The effect of MA process parameters on the alloying effect was analyzed and the effect of sintering temperature on the microstructure and properties of the sintered body was studied. The oxidation resistance of the alloy at high temperature was studied by oxidation experiment. The effects of different MA factors on the powder alloying effect of 9Cr-ODS RAFM steel were studied, including ball milling time, ball to weight ratio (BPRR) and process control agent process control (PCA). X-ray diffractometer and scanning electron microscope (SEM) were used to analyze the phase and morphology of the powder. The results show that the alloy degree increases with the prolongation of ball milling time and the increase of ball milling time, and the addition of PCA is beneficial to the increase of powder yield and the reduction of cold welding phenomenon and the hardness of powder. The effect of sintering temperature on the densification and properties of the alloy was investigated. The microstructure and microstructure of the sintered body and the tensile strength of the sintered material were analyzed and tested by means of optical microscope, energy spectrum analyzer (EDS), tensile tester and so on. The results show that the relative density and tensile strength of the sintered samples increase with the increase of sintering temperature. When the sintering temperature is 1390 鈩，

本文编号：2032984