Ni—12Co—5Al合金的超塑变形

采用合适的冶炼及形变热处理工艺获得了具有超细化α－Ｔｉ／Ｔｉ２Ｃｏ双相组织的Ｔｉ－１２Ｃｏ－５Ａｌ合金板材，该合金呈现出优异的高速低温超塑性，在７００℃和３×１０＾－２ｓ＾－１的高应变速率条件下延伸率超过２０００％。微观组织研究表明超塑变形促进了Ｔｉ２Ｃｏ粒子的长大和形状变化，在塑性应变高达１５５０％时试样中仍无孔洞产生，应变硬化和应变速率硬化的共同作用是该合金具有优异超塑性的根本原因。     

Ti－24Al－14Nb－3V－0．5Mo合金的超塑性

研究了温度及应变速率对Ｔｉ－２４Ａｌ－１４Ｎｂ－３Ｖ－０．５Ｍｏ（ａｔ．－％）合金超塑性能的影响．试验结果表明，在９８０℃，３．５×１０~（－４）ｓ~（－１）的最佳超塑变形条件下，合金显示出较高的超塑性；应变速率敏感性指数ｍ为０．６９，拉伸延伸率Ｅｌ．为８１８％．根据其细小的α_２＋β_０两相组织和等温拉伸的试验方法，确定合金的超塑性属于细晶组织超塑性．在超塑变形过程中，合金无空洞产生，显微组织发生动态粗化．     

Ti—24Al—14Nb—3V—0.5Mo合金的超塑性

研究了温度及应变速率对Ｔｉ－２４Ａｌ－１４Ｎｂ－３Ｖ－０．５Ｍｏ（ａｔ－％）合金超塑性能的影响。试验结果表明，在９８０℃，３．５×１０＾－＾４ｓ＾－＾１的最佳超塑变形条件下，合金显示出较高的超塑性；应变速率敏感性指数ｍ为０．６９，拉伸延伸率Ｅｌ．为８１８％。根据其细小的α２＋β０两相组织和等温拉伸的试验方法，确定合金的超塑性属于细晶组织超塑性。在超塑变形过程中，合金无空洞产生，显微组织发生动态粗化     

Ti—Mo—TiC烧结合金中TiC的腐蚀行为

纯钛虽说具有良好的耐蚀性,但对盐酸、硫酸等非氧化性酸的耐蚀性却不大好．在钛中添加２５％以上的钼时,对这些酸的耐蚀性可有实质上的改进．但这种钛钼合金熔炼时易偏析,因此开发了粉末冶金的Ｔｉ－３０％Ｍｏ合金,并在其中添加碳化物,以提高硬度和耐磨性,如Ｔｉ－Ｍｏ－（３３％～４５％） ＴｉＣ合金等．为明了合金中ＴｉＣ的腐蚀机制,用电位学方法研究了由β－Ｔｉ和ＴｉＣ两相构成的Ｔｉ－Ｍｏ－ＴｉＣ 烧结合金中的硬质相ＴｉＣ在几种酸碱溶液中的腐蚀行为． 使用的试样为Ｔｉ－２０％Ｍｏ－３３％ＴｉＣ合金（ＴＭ－２）和不…     

应用d－电子合金设计理论发展新型抗热腐蚀单晶镍基高温合金──Ⅲ．性能评价

根据ｄ－电子合金理论研究了合金系统Ｎｉ－１６Ｃｒ－９Ａ１－２Ｗ－１Ｍｏ－４Ｃｏ－Ｔｉ－Ｔａ－Ｎｂ（ａｔ．－％）的热腐蚀行为。选择了最佳成分范围内的４种成分进行单晶生长及性能评价。确定了性能匹配最佳的合金成分（ａｔ．－％）为：Ｎｉ－１６Ｃｒ－９Ａ１－２Ｗ－１Ｍｏ－４Ｃｏ－３．１２５Ｔｉ－０．８７５Ｔａ。完成了整个合金设计过程．该合金抗热腐蚀能力达到或超过ＩＮ７３８ＬＣ，使用温度比ＩＮ７３８ＬＣ高７０－９０℃，其持久强度达到ＣＭＳＸ－２的水平，试验证明ｄ－电子合金设计理论可以用于研制开发高性能抗热腐蚀单晶镍基高温合金．     

APPLICATIONS OF d-ELECTRONS ALLOY DESIGN THEORY TO DEVELOPMENT OF HOT CORROSION RESISTANT Ni－BASE SINGLE CRYSTAL SUPERALLOYS Ⅲ. Characterization of Properties

根据ｄ－电子合金理论研究了合金系统Ｎｉ－１６Ｃｒ－９Ａ１－２Ｗ－１Ｍｏ－４Ｃｏ－Ｔｉ－Ｔａ－Ｎｂ（ａｔ．－％）的热腐蚀行为。选择了最佳成分范围内的４种成分进行单晶生长及性能评价。确定了性能匹配最佳的合金成分（ａｔ．－％）为：Ｎｉ－１６Ｃｒ－９Ａ１－２Ｗ－１Ｍｏ－４Ｃｏ－３．１２５Ｔｉ－０．８７５Ｔａ。完成了整个合金设计过程．该合金抗热腐蚀能力达到或超过ＩＮ７３８ＬＣ，使用温度比ＩＮ７３８ＬＣ高７０－９０℃，其持久强度达到ＣＭＳＸ－２的水平，试验证明ｄ－电子合金设计理论可以用于研制开发高性能抗热腐蚀单晶镍基高温合金．     

Ni－Ti－Nb宽滞后记忆合金的显微组织和力学性能

用金相显微镜、电子探针及低温拉伸试验研究了采用不同熔炼方法获得的Ｎｉ－Ｔｉ－Ｎｂ宽滞后记忆合金的显微组织和力学性能。结果表明，熔炼方法不同会影响合金铸锭中的Ｃ、Ｏ含量；随合金中Ｃ、Ｏ等间隙原子含量的增高，（Ｔｉ，Ｎｂ）＿２Ｎｉ相增多，并趋于呈偏聚态分布，明显降低合金的塑性。（Ｔｉ，Ｎｂ）＿２Ｎｉ相的含量和分布形态是影响合金力学性能的主要因素。     

恒温锻造Ti－Al－Nb－Cr－V系（γ＋α_2）合金的热处理组织

研究了Ｔｉ－４７Ａｌ合金添加少量Ｎｂ、Ｃｒ、Ｖ元素（１ａｔ％－２ａｔ％）并经恒温锻造后，在不同热处理制度下的显微组织特征，以及Ｎｂ、Ｃｒ、Ｖ对合金组织的影响。结果表明，Ｔｉ－４７Ａｌ－２Ｎｂ－１Ｃｒ－１Ｖ及Ｔｉ－４７Ａｌ－２Ｖ－１Ｃｒ合金的热处理组织形貌主要取决于高温处理的温度、在（γ＋α）两相区，稍低于Ｔａ温度处理时，α相显著粗化，随加热温度的降低，α、γ两相均明显细化，进一步降低加热温度，发生γ，相的明显粗化。通过控制高温加热温度及时间，可以有效地控制合金的组织，使其获得全片层、近片层、双态、近双态、近γ以及细化的近γ组织。     

共晶NiAl—9Mo合金的超塑性行为

研究了共晶 ＮｉＡｌ－９Ｍｏ合金的超塑性行为及其变形机制．该合金的微观组织由 ＮｉＡｌ以及 ＮｉＡｌ和α－Ｍｏ共晶体组成．在 １３２３－１３７３ Ｋ温度区间,以 ５.５５×１０－５－１．１１×１０－４ ｓ－１的应变速率拉伸变形时,表现出超塑性行为,最大延伸率达到 １８０％,应变速率敏感性指数达到 ０．５６．超塑性的变形机制为初生 ＮｉＡｌ基体的晶界滑动,断裂起源于超塑性变形过程中产生的孔洞．     

大晶粒含钛Fe－36．5Al基合金的超塑性研究

通过对未加Ｔｉ及加有不同量Ｔｉ的Ｆｅ－３６．５Ａｌ（原子分数，％）基合金的高温变形行为的研究，发现加Ｔｉ的合金在９００—１０００℃，初始应变速率为２．０８×１０￣（－４）－８．３３×１０￣（－２）ｓ￣（－１）范围内比未加Ｔｉ的ＦｅＡｌ合金的延伸率有较大幅度提高，且应变速率敏感性指数ｍ值普遍超过０．３。随含Ｔｉ量的增加，ｍ值及延伸率也普遍提高，最高值分别达到０．４３和２９７％．金相及ＴＥＭ分析表明，变形过程中出现了明显的晶粒细化及亚晶形成过程，并由此导致了大晶粒含钛ＦｅＡｌ基合金的超塑性。     

新型的治疗阿尔茨海默氏症药物(1-二甲基磷酰基-2,2,2-三氯)-乙基-1-醇烟酸醋对体外神经细胞的作用

目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基^-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L^-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L^-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L^-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。     

Rheology Feature of Simple Metal Melt

The rheology feature of Sb, Bi melt and alloys was studied using coaxial cylinder high-temperature viscometer. The results showed that the curve of torsion-rotational speed for Sb melt presents a linear relation in all measured temperature ranges, whereas for the Bi melt, the curve presents obvious non-Newtonian feature within the low temperature range and at relative high shear stress. The rheology feature of Sb80Bi20 and Sb20Bi80 alloy melts was well correlated with that of Sb and Bi, respectively. It is considered that the rheology behavior of Sb melt plays a crucial role in Sb80Bi20 alloy and that of Bi melt plays a crucial role in Sb20Bi80 alloy.     

Microstructures and Mechanical Properties of a Newly Developed Austenitic Heat Resistant Steel

The effect of heat treatment on the microstructures and mechanical properties of a newly developed austenitic heat resistant steel(named as T8 alloy) for ultra-supercritical applications have been studied. Results show that the main phases in the alloy after solution treatment are γ and primary MX. Subsequent aging treatment causes the precipitation of M_(23)C_6 carbides along the grain boundaries and a small number of nanoscale MX inside the grains. In addition, with increasing the aging temperature and time, the morphology of M_(23)C_6 carbides changes from semi-continuous chain to continuous network.Compared with a commercial HR3C alloy, T8 alloy has comparable tensile strength, but higher stress rupture strength. The dominant cracking mechanism of the alloy during tensile test at room temperature is transgranular, while at high temperature, intergranular cracking becomes the main cracking mode, which may be caused by the precipitation of continuous M_(23)C_6 carbides along the grain boundaries. Typical intergranular cracking is the dominant cracking mode of the alloy at all stress rupture tests.     

Three-Dimensional Growth of Coherent Ferrite in Austenite: A Molecular Dynamics Study

Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.     

The 15th Global Foundry Sourcing Conference 2014held in Qingdao China

Organized by Suppliers China Co., Ltd and co-organized by the National Technical Committee 54 on Foundry of Standardization Administration of China, the 15th Global Foundry Sourcing Conference 2014 （hereinafter referred to as FSC 2014） was successfully held on Sep. 23rd in Grand Regency Hotel, Qingdao. More than 500 delegates from home and abroad attended this conference, including over 130 purchasers from 20 countries and 380 domestic and foreign suppliers.     

Secondary Recrystallization Behaviors of Grain-Oriented 6.5 wt% Silicon Steel Sheets Produced by Rolling and Nitriding Processes

By rolling and nitriding processes, 0.23- to 0.3-mm-thick grain-oriented 6.5 wt% silicon steel sheets were produced. The core losses of grain-oriented 6.5 wt% silicon steel at frequencies ranging from 400 Hz to 20 k Hz were lower than that of the grain-oriented 3 wt% silicon steel with the same thickness by 16.6–35.8%. The secondary recrystallization behavior was investigated by scanning electron microscopy, energy-dispersive spectroscopy, and electron backscattered diffraction. The results show that the secondary recrystallization in high-silicon steel sheets develops more completely as the nitrogen content increases after nitriding, secondary recrystallized grain sizes become larger, and the sharpness of Goss texture increases. Because more {110}116 grains in the subsurface and the central layer of the sheets have a lot of 20°–45° high-energy boundaries in addition to Goss grains, {110}116 can be the main component through selective growth during secondary recrystallization when the inhibitor quantity is not enough and inhibitor intensity is weaker. The increases in nitrogen content can increase the inhibitor intensity and hinder abnormal growth of a mount of {110}116 grains and therefore enhance the sharpness of Goss texture.     

Laser Cladded TiCN Coatings on the Surface of Titanium

Laser cladded coatings of TiCN were produced on the surface of titanium. To obtain the optimal techniques, several conditions were tested by varying the laser scanning rate. The choice of shielding gas was also studied. The cladded coatings were then evaluated from the surface mechanics point of view based on their microhardness. The microstructure of some interesting samples was investigated by optical micrographs (OM). The results showed that under the condition of fixed pulse frequency and pulse width, the laser scanning rate and the shielding gas are the main factors influencing the components of coatings. TiCN coatings were decompounded and oxidized during the cladding process in the condition of no shielding gas of N2. X-ray diffraction results indicated that the composite coatings composed of TiCN, TiC, Ti2N, and TiO2 were produced using appropriate techniques. The results indicated that the best condition in terms of the surface microhardness is obtained when the scanning rate is 1.5mm / s, the pulse frequency is 15Hz, the pulse width is 3.0ms, and N2 is chosen as the shielding gas. The microhardness of the composite coatings is about 1331kg · mm - 2, which is about 4 times that of the substrate. The optical micrographs indicated that the cladding zone is made up of TiCN, TiO2, and some interdendritic Ti, but the diffusion zone mainly consists of the dendrites phase, and the cladded depth is about 80?滋m, which is more than 2 times that of the laser nitrided sample. There were no microcracks or air bubbles in the cladded sample, which was cladded using the above optimal techniques.     

Effect of Short-Time Aging on the Pitting Corrosion Behavior of a Novel Lean Duplex Stainless Steel 2002

The effect of short-time aging in the temperature range between 400 and 1000 °C on the pitting corrosion behavior and mechanical property of a novel lean duplex stainless steel(LDSS) 2002 was investigated through the potentiostatic critical pitting temperature(CPT) tests and the Charpy impact tests. Both the pitting corrosion resistance and the toughness of aged specimens degraded due to the precipitation of detrimental secondary phases and the most significant reduction of CPT and impact energy emerged at 650 °C concurrently. The CPT of LDSS 2002 specimen aged at 650 °C decreased by 28 °C, and the impact energy dropped from 69 to 29 J/cm~2 compared with the solution-annealed sample. Transmission electron microscopy characterization showed that the main precipitates in LDSS 2002 were Cr_2N and M_(23)C_6 along the ferrite–austenite grain boundaries.     

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正The Transactions of Nonferrous Metals Society of China,founded in 1991 and sponsored by The Nonferrous Metals Society of China,is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology,including mineral processing,extraction metallurgy,metallic materials and heat treatments,metal working,physical metallurgy,powder metallurgy,with the emphasis