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duplex microstructure with a grain spacing of 20-30 μm and a lamellar spacing of 10-20 nm. Furthermore, multiple microstructures of near gamma, nearly lamellar and fully lamellar were obtained through..., Bartolotta P A. Sheet gamma TiAl: status and opportunities [J]. Journal of Metals, 2004, 56(11): 42-45. [2] Kim Y W. Ordered intermetallic alloys. Part Ⅲ: Gamma titanium aluminides [J]. Journal......
). The relationship between the microstructure and the synthesis conditions was investigated by using XRD, TEM, SEM as well as BET analyzer. The results show that nano γ-Ni-28Fe alloy is composed of a gamma...-Ni-28Fe alloy by using mechanochemical alloying(MCA) process. The nano γ-Ni-28Fe powders show gamma phase (FCC structure), and its average grain size is measured as 20 nm. Magnetic measurements......
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. The equivalent load method was employed to account for random repeated loads in structural reliability analysis. Degradation of material strength was regarded as a Gamma process. The probabilistic......
基于近红外光谱的汽油辛烷值预测与模型优化韩仲志,万剑华,刘康炜中国石油大学(华东)地球科学学院摘 要:在波长120004000 cm-1范围内采集了60组汽油样品的近红外光谱数据,并基于此数据研究汽油辛烷值预测过程中的模型优化问题:采用五折交叉验证法,比较了最小均方二乘法(PLS),神经网络(ANN)和支持向量机(SVM)的辛烷值预测模型,发现SVM算法较稳定可靠,更适合于小样本情况下的光谱分析;SVM模型下分别采用网格寻优(Grid),遗传算法(GA)和粒子群算法(PSO)进行惩罚参数C和RBF核函数参数gamma两个参数优化,总体最佳M SE分别为0.00444,0.0038和0.03262,GA优化参数能力最强;基于GA参数优化下SVM模型,研究了主分量分析(PCA)和连续投影算法(SPA)的特......
for Radiation Protection摘 要:2.98 kGy/h(1007 h) gamma irradiation and 90 ℃(2000 h) thermal aging were exerted to X65 grade low carbon steel buried in Gaomiaozi......
and heating rate on differential thermal analysis (DTA) curves were investigated. Available methods for determining gamma prime (γ′) solvus, solidus and liquidus were analyzed and compared separately......
, the microstructure was duplex structure with some fine equiaxed gamma grains and thin needly TiB2 phases. With the SPS temperature increasing from 900 °C to 1000 °C, the micro-hardness was changed... plasma sintering (SPS) due to its specific characters [8-10]. In addition, the application of gamma TiAl alloys requires specific properties in different fields, for example, in aerospace fields excellent......
