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排序方式: 共有9783条查询结果,搜索用时 15 毫秒
111.
通过论述海绵钛反应机理,分析了镁法制取海绵钛生产液镁利用率低的形成原因,探索了提高镁利用率的途径,试验表明:提升后期反应液面,可以提高镁利用率,提高海绵钛单炉产能。 相似文献
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114.
MB2镁合金变形组织性能研究 总被引:4,自引:1,他引:4
为了探讨镁合金铸造组织在较低温度下变形时对组织性能的影响,采用现代冶金分析和测试方法,研究了MB2镁合金铸棒在不同变形温度和变形程度下组织演变过程和再结晶行为,并对各变形条件下试样进行拉伸实验.结果表明,通过挤压变形及动态再结晶,可以显著细化铸造MB2合金的晶粒,其尺寸可由铸态的约100 μm减少到5μm;随变形温度的升高,MB2合金的抗拉强度下降,达到一定温度后,趋于稳定;在相同的变形程度下,随着变形温度的升高,晶粒有长大的趋势. 相似文献
115.
镁合金及其在工业中的应用 总被引:46,自引:0,他引:46
镁在自然界中是大量存在的,是一种存储量十分丰富的元素。镁及其合金均具有很多优点,例如重量轻、比强度和比刚度高、消震性能好、优良的机械加工性能和抛光性能、无毒性、无磁性、高热导率、可回收利用等,已在汽车、计算机、移动电话、精密仪器、国防和航空航天等很多领域得到了广泛的应用,具有广阔的应用前景。详细介绍了镁合金的特点及其在工业中的应用情况。 相似文献
116.
论述了武钢一炼钢纯镁铁水脱硫工艺特点、脱硫机理及脱硫喷枪汽化室的作用原理,比较了各种主要铁水脱硫工艺效果。 相似文献
117.
Effects of RE on Microstructures and Mechanical Properties of Hot-Extruded AZ31 Magnesium Alloy 总被引:4,自引:2,他引:4
Effects of rare earth (RE) additions on microstructure and mechanical properties of the wrought AZ31 magnesium alloy were investigated. The results show that, by adding 0.3%, 0.6% and 1.0% RE elements, the as-cast microstructure can be refined, and the as-cast alloys‘ elongation and tensile strength can be improved. After extrusion, the alloy with 0.3 % and 0.6% RE additions obtain a finer microstructure and the best mechanical properties, but the alloy with 1.0% RE addition has the coarse A1-RE compound particles in grain boundaries which decreased elongation and tensile properties. Usually, Rare earth (RE) elements were used to improve the creep properties of aluminium-containing magnesium pressure die cast alloys at elevated temperatures. In this paper, it is also found that the high temperature strength of extruded materials can be increased by RE elements additions. 相似文献
118.
The green phosphor for white LED, Ca8Mg(SiO4)4Cl2∶Eu2+, Mn2+, was synthesized by high temperature solid state reaction under reducing atmosphere. During the process of the phosphor prepared, the excess CaCl2 can improve the intensity of emission. The experimental results indicate that there is an effective energy transfer from Eu2+ to Mn2+in Ca8Mg(SiO4)4Cl2 host. This kind of energy transfer may be due to resonance transfer, and this energy transfer is limited. 相似文献
119.
Julio Aguilar Martin Fehlbier Tilman Grimmig Horst Bramann Carsten Afrath Andreas Bührig‐Polaczek 《国际钢铁研究》2004,75(8-9):492-505
Semi‐solid metal casting is an innovative technology for the production of near‐net‐shape parts with demanding mechanical properties. The paper describes different processing routes and materials for semi‐solid‐metal casting (SSM), which have been investigated and also partially developed at the Foundry‐Institute of Aachen University. The standard thixocasting process for aluminium, highly reactive magnesium alloys and steel alloys with high melting points was investigated under variation of a wide range of process parameters. Specially adapted pre‐material production and reheating methods were developed for different materials and their application and future potential is pointed out. The thixocasting experiments were executed on a modified high pressure die‐casting machine with a specially designed “step‐die” providing wall thicknesses from 0.5 to 25 mm. The mechanical properties were tested in dependence of the wall thickness and the metal velocity. The results of these examination show high tensile strength values in combination with very good elongations. The rheocasting process is a new SSM‐forming method with liquid melt as feed‐stock and a high recycling potential. The research results of RCP‐technology (Rheo‐Container‐Process) invented at the Foundry‐Institute and of the Cooling‐Channel‐Process for aluminium and magnesium alloys are promising and are presented in this paper. Studies on semi‐solid processing of magnesium alloys and mixtures of them were conducted by ThixomoldingTM. To establish the most adequate process parameters, the temperature and the mixture relations were varied. Using a mould for tensile test specimens, the mechanical properties and the microstructure evolution could be evaluated. The chemical composition of the different phases was determined using SEM and EDX technologies. Evaluations of the flowing properties were conducted using a spiral mould with a total length of 2m and a cross section of 20mm x 1.5mm. 相似文献
120.
High resolution electron microscopy has been used to examine both the similarities and differences in the growth morphologies of Fe2O3, Cr2O3 as formed on iron alloys, and MgO as formed by burning Mg in moist air. A general discussion is also given of the relative advantages and disadvantages of a variety of TEM techniques as applicable to the study of oxidation phenomena. 相似文献