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氩气雾化FGH95高温合金粉末的分析研究 总被引:3,自引:0,他引:3
本文介绍对国内氩气雾化法生产的FGH95高温合金粉末的研究结果,并和美国Crucible公司用氩气雾化法生产的Rene95合金粉末进行了对比。结果表明,国产旋风分离器粉的粒度组成、松装密度、摇实密度都和美国粉相近,但球形度比美国粉稍差。粘聚程度较重,因而流动性较差;夹杂较多,但空心率和空心直径大于10μm的空心个数都比美国粉低;显微组织、偏析规律与美国粉相同。还观察了粉末经700℃至1200℃真空 相似文献
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根据孔隙材料及致密体的塑性变形理论,揭示了热等静压过程中粉末体及其包套的几何尺寸和相对密度的演化规律。在此基础上,提出了粉末体在圆柱形包套内均匀致密的判据,对包套尺寸的确定具有指导意义。应用本文提出的方法分析FGH95粉末高温合金热等静压过程,理论分析结果与试验数据吻合。 相似文献
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国内粉末高温合金涡轮盘件制造技术的发展现状 总被引:3,自引:1,他引:2
在介绍粉末高温合金涡轮盘主要成形工艺的基础上 ,综述了我国粉末高温合金盘件制造技术发展现状 ,对存在的问题提出了一些建议。 相似文献
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概述了国内外镍基粉末高温合金的发展、氩气雾化制粉技术的特点、氩气雾化镍基高温合金粉末的特性和增材制造用镍基高温合金粉末的发展方向,重点介绍了镍基高温合金粉末的形貌与粒度控制、氧化特性、气体脱附行为和缺陷形成及控制措施。讨论了镍基高温合金粉末特性与合金缺陷之间的内在关系,总结了缺陷消除措施的研究进展,明确了未来粉末涡轮盘用氩气雾化镍基高温合金粉末质量优化的发展方向,并对高品质氩气雾化镍基高温合金粉末促进增材制造技术在航空航天领域的应用进行了展望。 相似文献
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实验结果表明,对PREP法FGH95合金粉末进行预热处理。可以使亚稳碳化物(MC’)向稳定型的MC、M23C6、M6C型碳化物转变,明显改变碳化物的分布状态,有效地抑制PPB的形成。 相似文献
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为探索多火次等温锻造对新型粉末高温合金晶粒细化的影响, 本文对实验合金进行了每火次变形量40%左右的三火次等温锻造, 采用商用有限元软件DEFORM 2D模拟锻造过程中的等效应变分布图, 采用电子背散射衍射技术对各火次后的锻坯进行显微组织观察和分析.研究表明: 等温锻造过程中, 锻坯轴向剖面大致分为三个区域, 位于上、下两端面附近的Ⅰ区变形量最小, 位于两侧附近的Ⅱ区次之, 位于剖面中心的Ⅲ区变形程度最大.经过三火次等温锻造后, 锻坯Ⅱ、Ⅲ区再结晶充分, 获得等轴细晶组织, 平均晶粒尺寸2~3 μm.然而Ⅰ区形成再结晶不完全的"项链"组织, 在变形晶粒周围分布大量细小的再结晶晶粒, 变形晶粒内小角度晶界含量较多, 位错密度较高.通过对三火次后的锻坯进行合适的热处理, Ⅰ区"项链"组织得到细化, Ⅱ、Ⅲ区组织发生晶粒长大, 整个盘坯为较均匀的细晶组织, 平均晶粒尺寸为6~8 μm. 相似文献
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本文研究了新型第四代粉末高温合金FGH4102在等温热模拟压缩过程中的组织演变,对γ′相在动态再结晶过程中的作用进行了探讨。结果表明,热等静压态合金在1060~1120℃温度范围变形时,热加工性能较好。1140℃变形后试样容易发生开裂,合金热加工性能较差。合金在γ+γ′两相区变形时均发生了不同程度的动态再结晶,再结晶晶粒尺寸远小于热等静压态的晶粒尺寸。变形过程中,尺寸较大的γ′相起到促进动态再结晶的作用。变形参数对动态再结晶的影响非常显著。低温高应变速率变形时,γ′相促进动态再结晶形核占主导地位,再结晶晶粒比较细小;高温低应变速率变形时,晶粒长大逐渐占据主导地位,再结晶晶粒尺寸较大。 相似文献
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The potential of spray forming for microstructural refining can be attractive to the production of superalloys. A 200 mm spray formed FGH95 superalloy round billet that was produced using a single atomizer has considerably homogeneous, small, equiaxed grains. The measured oxygen content is 2×10-5, and the measured porosity is only 0. 6%. The achieved yield of deposit is in a good range of about 73. 6%. The microstructure and tensile properties of nickel-based spray formed FGH95 superalloy are analyzed. Also, effects of heat treatment on microstructure were discussed. The results show that the spray formed FGH95 superalloy has higher isotropy in tensile property due to its γ′ phase homogeneous distribution and less defects in the microstructure. Regarding processing procedures, the different heat treatment processes affect the microstructure and γ′ phase homogeneous distribution of spray formed FGH95 superalloy. 相似文献
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FGH 95 is a powder metallurgy (P/M) processed superalloy,which was developed in the 1980s in China.One of the applications of FGH 95 was high pressure turbine blade retainers.The manufacturing processes used to produce FGH 95 blade retainers consisted of atomization by plasma rotating electrode process (PREP),hot isostatic pressing (HIP) at super-solvus temperature and a sub-solvus solution heat treatment.The material had an equiaxed grain structure (ASTM 6.5-7.5).The γ′ precipitates in as-HIP FGH 95 showed a tri-model distribution.Carbides in the alloy were MC type and precipitated at grain boundaries.The prior particle boundaries (PPB) in the material originated mainly from γ′ phase.Statistics of the mechanical properties data from batch production of the FGH 95 blade retainers were investigated.The as-HIP FGH 95 blade retainers showed high strength at room temperature and 650 ℃,excellent creep resistance and outstanding stress rupture strength at 650 ℃. 相似文献
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The need for nickel-base powder metallurgy (PM) superalloy turbine discs is becoming increasingly evi dent. With the eventual aim of improving thrust-to-weight ratio of aeroengines for power generation, well integration of significantly high strength, high damage tolerance and high-temperature capability would be reasonably required. An advanced PM superalloy, which was designed for applications up to 815- 8 5 0 ℃, was experimentally investigated. Emphasis was primarily put on microstructure and mechanical properties. The results indicated the measured phases in the sample were composed of γ,γ', MC, and Ma B2. With uniform coarse grain microstruc ture (ASTM 5-6), the sample appeared to exhibit overwhelming superiority over the prior art materials FGH95, FGH96, FGH97 and FGH98. The dominant embodiments consisted of high tensile strength (Rm = 1000 MPa and Rp0.2 800 MPa at 850℃), strong creep resistance (ξp 0.12% at 815 ℃/400 MPa/50 h), and considerable stressrupture life (τ=457.4 h at 815 ℃/450 MPa). The technical practicability of applications up to 815-850 ℃ of this alloy was conclusively proved. 相似文献
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Niranjan Das 《Transactions of the Indian Institute of Metals》2010,63(2-3):265-274
Nickel-based superalloys have served as the most competitive high temperature structural materials under highly stressed and aggressive operating conditions in a variety of applications for more than 60 years. The most demanding among all the applications has been the gas turbine aerofoil castings of modern aero-engines. These turbine parts operate in extremely aggressive environment of high velocity hot combustion gas-air mixture carrying highly corrosive ingredients at high pressure. Gas turbine aerofoil materials should therefore possess adequate resistance to creep, fatigue and aggressive environment. Materials design for such application therefore has been extremely challenging, particularly since the engine designers always aim at higher turbine entry temperature (TET) in order to achieve greater engine thrust and better fuel efficiency. In spite of enormous efforts made in the recent past towards developing ceramics and their composites, Ni-based superalloys continue to be most reliable blade and vane materials offering always the highest TET. This has been possible through better alloy design, improved blade cooling schemes, protective coatings and directional solidification (DS) of either columnar grains or single crystals (SC) along the most favorable 〈001〉 texture. During the last six decades, TET has gone up by about 500K. This article covers recent advances in cast Ni-based superalloys, including our own efforts in this direction. Extensive research at DMRL has led to the development of new generation Ni-based superalloys, designated as DMD-4 and DMS-4 for DS and SC processing, respectively. Simultaneously, expertise has been developed to cast DS and SC components for aero-engines. Technology has also been established for pilot scale production of these components. 相似文献