GH2132合金组织和性能的研究

IMR OpenIR

	GH2132合金组织和性能的研究
	陈琪
学位类型	硕士
导师	孔凡亚
	2012
学位授予单位	中国科学院金属研究所
学位授予地点	北京
学位专业	材料工程
关键词	紧固件抗拉强度热轧冷拔热处理 Fasters Tensile Strength Hot Rolling Cold Drawing Heat Treatment
摘要	" GH2132合金是一种25Ni-15Cr-Fe基变形高温合金，它以优良的耐腐蚀和抗松弛能力被广泛应用于航空紧固件。随着我国航空工业的飞速发展，由于使用需要，对用于连接各种零件的紧固件性能要求越来越高，迫切需要1100MPa强度级别的GH2132合金紧固件。因此，为了提高GH2132合金的抗拉强度，本文重点从变形和热处理这两个工艺出发，同时采用光学显微镜和扫描电镜对组织作机理分析，以性能测试作鉴定手段来获得一套优化的生产工艺。变形采用热轧和冷拔两种方式，其中冷拔是在热轧的基础上进行的，通过变形可以控制合金的晶粒大小和所需要的尺寸，变形后的热处理一方面用来改善变形后的组织缺陷，获得均匀细小的晶粒度，另一方面通过控制析出相γˊ来获得沉淀强化，以保证细小弥散析出相γˊ的同时，防止晶粒度长大。此研究重点从固溶和时效两方面来研究热处理制度，选取不同固溶﹑时效的温度和时间来观察其对机械性能的影响，最终分别得到优化的热加工和冷加工后的热处理工艺。研究结果表明，热轧可以使晶粒细化到10级以上，热轧后优化的热处理热处理制度为：900℃固溶2.5h，油冷；710℃时效16h,空冷。通过这两种工艺的结合能将GH2132合金的抗拉强度提高到1120MPa，屈服强度到800MPa，并保持良好的塑性。冷拔进一步细化晶粒，还可以产生一定程度的加工硬化，冷变形后经过热处理来改善组织均匀性与综合性能，分别对两种热处理方式进行了研究：一是固溶+时效热处理方式，优化的热处理热处理制度为：900℃固溶2.5h，油冷，720℃，16h＋660℃，16h空冷，能保证δ＞20%时，将GH2132合金的抗拉强度提高到1250MPa；二是直接时效热处理方式，优化的热处理热处理制度为：680℃直接时效，能保证δ＞13%时，将GH2132合金的抗拉强度提高到1400MPa。
其他摘要	" GH2132 alloy is a 25Ni-15Cr-Fe base super alloy, for its good corrosion resistance and special property of anti-relaxation, which is widely used for fastening pieces in the area of aviation. With rapid development of industry of aviation, further improvement of mechanical properties is highly required for the fasters serving to link all kinds of pieces in engine, which of strength have to above 1100MPa. In order to attain the requirement of property, the study was taken on the two aspects: deformation and heat treatment, at the same time, the optical microscope and scanning electron microscope have been used to analysis basic theory by investigating microstructures, and mechanical properties were checked as the ultra aim to meliorate the process of producing. Heat rolling and cold drawing were the main processes of deformation, and Heat rolling was the basis of cold drawing, by the mean of deformation, grain size and required diameter size could be controlled. Heat treatment had two effects after deformation, one was used to refine the microstructures to homogenize the alloy, in the other hand, GH2132 alloy could be hardened by aging with γ′ precipitated phase. The study of heat treatment could be divided to two aspects: solution and aging, different time and temperature of which was selected to taken on the alloy to see what process benefited the heat rolling and cold-drawn alloy significantly respectively. The results indicate that the grain size of GH2132 alloy could be refined to up 10 grade after the heat rolling, and the suitable heat treatment was annealed at 900℃ for 2.5 hours, oil quenched, and then aged at 710℃ for 16 hours, air cooled. The tensile strength, which was treated with the both processes above continuously, could attain to 1120MPa with the yield strength beyond 800MPa, while other tensile properties worked well. Cold drawing could be used to refine the grain size deeply, moreover, GH2132 alloy could be strengthened by work hardening, heat treatment was taken to homogenize the alloy and meliorate the comprehensive properties after the process of deformation, two means of heat treatment were studied on the alloy: one was solution with aging, the suitable process was solution at 900℃ for 2.5 hours, oil quenched, and then aged at 720℃ for 16 hours, air cooled, as well as 660℃ for 16 hours, air cooled, the strength of GH2132 alloy could be attained to 1250MPa while δ﹥20%, the other was direct aging, the suitable process was aged at 680℃ for 16 hours directly, the strength can be over 1400MPa while δ﹥13%.
文献类型	学位论文
条目标识符	http://ir.imr.ac.cn/handle/321006/64542
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	陈琪. GH2132合金组织和性能的研究[D]. 北京. 中国科学院金属研究所,2012.