Mg,Ca,Y,La和Ce在Ni3Al中的合金化行为

利用Ｘ射线衍射法确定了合金元素Ｍｇ，Ｃａ，Ｙ，Ｌａ及Ｃｅ在Ｎｉ３Ａｌ中的合金化行为。结果表明，Ｍｇ，Ｃａ，Ｙ，Ｌａ及Ｃｅ原子占据Ｎｉ３Ａｌ中的Ａｌ位，并按以下顺序增加Ｎｉ３Ａｌ的有序度：Ｍｇ，Ｃａ，Ｙ和Ｌａ－Ｃｅ。随着合金元素含量的增加，Ｎｉ３Ａｌ的点阵常数亦按Ｍｇ，Ｃａ，Ｙ，Ｌａ－Ｃｅ的顺序呈线性增大。     

W、Nb对Fe76.5Cu1Si13.5B9非晶合金晶化行为的影响

用热分析法结合ＸＲＤ、ＴＥＭ研究了添加元素Ｗ、Ｎｂ对Ｆｅ７６．５Ｃｕ１Ｓｉ１３．５Ｂ９非晶合金晶化行为的影响。结果表明,Ｗ或Ｎｂ的加入都降低了Ｆｅ－Ｃｕ－Ｓｉ－Ｂ非晶合金反应的Ａｖｒａｍｉ指数ｎ;并且添加元素Ｎｂ更有利于该合金获得较小的ａ－Ｆｅ（Ｓｉ）晶粒。     

Ti,Ce和Mg对Zn-Al合金固态相变的影响

研究在Ｚｎ－Ａｌ合金中分别加入Ｔｉ,Ｃｅ和Ｍｇ等元素,对合金固态相变的影响。研究结果表明：Ｔｉ,Ｃｅ和Ｍｇ对Ｚｎ－Ａｌ合金人工时效时的沉淀析出起到不同程度的抑制作用。     

大块非晶Fe-Al-Ga-P-C-B-Si合金的热稳定性和磁性

大块非晶Ｆｅ┐Ａｌ┐Ｇａ┐Ｐ┐Ｃ┐Ｂ┐Ｓｉ合金的热稳定性和磁性近年来发现了一系列具有大玻璃形成能力的多元系非晶合金，如Ｍｇ－Ｌｎ－（Ｎｉ，Ｃｕ）、Ｌｎ－Ａｌ－ＴＭ、Ｚｒ－Ａｌ－ＴＭ、Ｚｒ－Ｔｉ－Ａｌ－ＴＭ、Ｚｒ－Ｔｉ－ＴＭ－Ｂｅ、Ｐｄ－Ｃｕ－Ｎｉ－Ｐ...     

Nd-Fe-Co-Cu-Nb-B系交换弹力磁体

Ｎｄ－Ｆｅ－Ｃｏ－Ｃｕ－Ｎｂ－Ｂ系交换弹力磁体以前的研究报道指出Ｎｄ－Ｆｅ－Ｂ系合金交换弹力磁体,通过添加Ａｌ、Ｓｉ、Ｖ、Ｃｒ、Ｇａ、Ａｕ、Ａｇ可获得１Ｔ以上的高剩余磁通密度。本文作者研究了Ｎｄ－Ｆｅ－Ｂ系合金添加Ｃｕ、Ｎｂ、Ｃｏ置换一部分Ｆｅ后对其...     

快凝的高剩磁Nd_5Fe_（71．5）CO_5B_（18．5）M合金的微结构和磁

快凝的高剩磁Ｎｄ_５Ｆｅ_（７１．５）ＣＯ_５Ｂ_（１８．５）Ｍ合金的微结构和磁性日本住友特殊金属公司开发一种快速凝固和晶化的高剩磁Ｎｄ５Ｆｅ７１．５Ｃｄ５Ｂ１８．５Ｍ合金，Ｍ＝Ａ１，Ｓｉ，Ｇａ，Ｃｕ，Ａｇ和Ａｕ。这种材料是基于Ｆｅ３Ｂ－Ｎｄ２Ｆｅ１４Ｂ...     

铸态高强度QT700-2球墨铸铁的研制(摘要)

介绍获得铸态ＱＴ７００－２球墨铸铁的生产方法：１原铁液在７ｔ／ｈ水冷冲天炉内熔化，出铁温度１４２０～１４８０℃；炉内用２％ＣａＣ２脱硫，炉前用Ｎａ２ＣＯ３进行包内脱硫，使Ｓ原≤０．０３５％。２球化剂为ＦｅＳｉｍｇ１０Ｒｅ９，孕育剂为７５ＦｅＳｉ，Ｓｉ－Ｂａ合金和Ｓｉ－Ｂｉ合金粉剂。采用凹坑式浇包冲入法进行球化处理，球化剂加入量为铁液量的１．４～１．６％，处理时同时加入Ｃｕ、Ｓｎ、Ｍｏ等合金元素和Ｓｉ－Ｂｉ粉剂，球化处理后加入小剂量硅铁粒和自制复合孕育粉剂进行二次孕育，随后用Ｓｉ－Ｂａ合金进行浮硅…     

Be对铸造Mg合金组织和力学性能的影响

研究了在Ｍｇ－９Ａｌ－０．５Ｚｎ－１ＲＥ合金中添加Ｂｅ后合金组织和力学性能的变化规律。Ｂｅ的加入对γ相有一一的变质作用，相的形状和分布随Ｂｅ含量的变化而变化。Ｂｅ的加入量少时，合金铁常温抗拉强度σｂ，σ０．２与伸长率δ都有所下降；当Ｂｅ的加入量增加到一定程度时，这些性能指标反而升高。继续加入是地，性能又会下降。高温拉伸性能的变化趋势与常温时相同，Ｂｅ的另入时对α－Ｍｇ基体的显微硬度影响不大。     

Al,Be含量对Cu-Al-Be-X合金相变点的影响

本文采用电阻－温度测试仪，系统地研究了合金元素Ａｌ、Ｂｅ含量对Ｃｕ－Ａｌ－Ｂｅ－Ｘ合金相变点的影响。结果表明，该合金在一定成分范围内，随着合金元素Ａｌ、Ｂｅ含量的增加，相变点Ａｓ、Ａｆ、Ｍｓ、Ｍｆ均下降，尤其是对Ｂｅ含量更加敏感。     

用于铸造关键部件的铝合金

本文讨论了一种在Ａｌ２８合金基础上开发的铝合金,它含４－５～５－８Ｍｇ,０－４～０－８Ｍｎ,０－０５～０－０８Ｔｉ和０－０２～０－０６Ｂｅ。该合金在铍熔解期间形成致密的Ｂｅ－Ｍｇ氧化物膜,它可防止金属铝被氧化。该合金的组织特征为铝的α固溶体加上以金属间化合物形式存在的夹杂物（Ｂ－Ｍｇ２Ａｌ３,ＦｅＡｌ,ＭｇＳｉ,Ｍｇ２Ｓｉ）。可用该合金来生产导弹反冲系统中所需的可靠且耐用的铸造部件。用于铸造关键部件的铝合金@尹丹     

Effect of be addition on the oxidation behavior of Mg−Ca alloys at elevated temperature

Beryllium was added to Mg−Ca alloys to study their ignition-proof properties. The ignition temperatures of Mg−2Ca alloys were increased dramatically with increasing Be addition. Thermogravimetric measurement revealed that the oxidation of Mg−2Ca alloys was slowed down by Be addition. After elevated temperature exposure to air, the Mg−2Ca alloy was partially ignited, while the surface of Be-containing alloys was smooth without any partial ignition. SEM, low-angle XRD, and AES observations indicated that the surface of Becontaining alloys became compact and dense, and the oxide film formed at elevated temperature mainly consisted of CaO together with MgO and BeO. It was found that the CaO enriched oxide layer acted as an impermeable barrier to the inward diffusion of oxygen and thus further oxidation was prevented.     

Effect of Ca addition on the oxidation resistance of AZ91 magnesium alloys at elevated temperatures

AZ91 magnesium alloys containing 0.27–5.22 wt.% Ca, were melted and cast to study the effects of Ca addition on oxidation resistance at elevated temperatures. An ignition temperature test showed that the ignition of AZ91 alloy occurred at about 350–450 °C below the melting point, whereas that of the Ca-containing AZ91 alloys did so at above 650 °C. Weight gain measurements indicated that the oxidation resistance of the AZ91 alloys improved with Ca addition. The oxidation rate was dependent on the oxidation temperature. In the temperature range of 300–400 °C, the oxidation rate increased linearly. By contrast, the weight of 5 wt.% Ca-containing AZ91 alloy increased slowly due to the formation of a protective oxide layer. The oxidized surfaces were analyzed with low-angle XRD, FE-SEM equipped with EDS and AES. Complex structures were found in the oxide layers of the Ca-containing alloys: the outer layer mainly consisted of CaO, which was of uniform thickness, and the inner layer was a mixture of CaO, MgO, and Al₂O₃. In contrast to the loose and porous MgO formed on the surface of AZ91, the compact and dense oxide layers acted as an effective barrier to the further oxidation of the Ca-containing AZ91 alloys.     

镁合金抗氧化及合金化阻燃研究进展

综述了镁合金氧化燃烧及燃点的测定方法、镁合金抗氧化和阻燃机理及合金元素(Ca，Be，RE，Y)对镁合金阻燃性能影响的研究现状。介绍了抗氧化和阻燃镁合金研制进展及应用现状，指出了研究中存在的问题及发展方向。     

Characterization of protective oxide layers formed on molten AZ91 alloy containing Ca and Be

AZ91 alloy in its molten state oxidizes rapidly in atmospheric conditions and begin to burn from the melt surface. In order to prevent the molten AZ91 alloy from burning, it is usually protected by a cover gas such as sulfur hexafluoride (SF₆). However, the use of SF₆ gas poses a serious threat to the environment as it is widely acknowledged to contribute to the global warming effect. Thus, several types of studies aimed at controlling the oxidation behavior of molten magnesium alloys have been carried out. This paper describes the characteristics of the oxide layers formed on molten AZ91 alloys containing Ca and Be. The surface analysis technique of GDS (Glow Discharge Spectroscopy) was used to investigate the oxide layers of AZ91 alloys containing Ca and Be. The GDS results showed that the oxide layer consists of CaO, MgO, BeO and Al₂O₃.     

On ignition point of Mg-Ca alloy under nitrogen atmosphere

The production cost will be greatly reduced if nitrogen can be used instead of inert gas in the spray forming process of magnesium alloys,but the heat from the reaction between magnesium alloys and nitrogen makes magnesium alloy burn easily.To solve the problem above,the ignition point of Mg-Ca alloy under nitrogen atmosphere was studied using a home-made experimental device and DSC-DTA.Results show that under nitrogen atmosphere,Ca addition has a great effect on the ignition point of Mg alloy.The ignition point of the Mg-5Ca bulk even exceeds 1,030 ℃,and the alloy can be held for 30 min at 900℃ without burning; while the average ignition point of Mg-5Ca powders is lower than 700℃,and it increases with the increasing particle size.Moreover,the purity of nitrogen must be in a certain scope; Mg-Ca alloy shows a higher ignition point under nitrogen with a purity of 99.5％.Based on the experimental results,the best adding content of Ca and the purity of nitrogen were determined,and the security and economic performance of preparing magnesium alloys by spray deposition were improved with nitrogen as atomizing gas.     

Ca和Ba对镁合金AZ63的燃点与熔体粘度的影响

研究了合金元素Ca和Ba对镁合金AZ63的燃点与熔体粘度的影响.结果表明:随着Ca或Ba量的增加,镁合金的燃点逐渐增大;随着温度的降低,镁合金熔体的动力粘度逐步增加,并且在963 K处降低;加Ba和加Ca的AZ63的燃点与粘滞性之间存在着某种关系,即粘滞性增大,镁合金燃点则提高.因此,可以通过测定不同的合金元素与镁合金的粘滞性的关系来判断该元素的阻燃作用,这是一条寻找有效阻燃合金元素的新思路.     

Ca合金化在镁合金中的作用

钙加入镁合金中可以提高合金的燃点;少量的钙加入镁合金中,可以显著提高镁合金在高温下的抗氧化性;钙对不同系列镁合金力学性能的影响不尽相同;钙合金化可以改善镁合金的高温性能及蠕变性能;钙是提高镁合金耐蚀性的有效合金元素,含钙镁合金有望成为新型的轻质耐高温材料。     

Effect of Ca and Y additions on oxidation behavior of AZ91 alloy at elevated temperatures

In order to develop the ignition-proof magnesium alloy, the effect of alloying elements, Ca and Y, on the oxidation behavior of AZ91 magnesium alloy at elevated temperatures was investigated. The ignition-proof performance, oxide products and oxidation kinetics of Ca- and Y-containing AZ91 alloys were studied. The results indicate that the proper addition of Ca can increase the ignition point of AZ91 alloy greatly. However, the oxide film of Ca-bearing AZ91 alloy formed at elevated temperature is thick and brittle, which is prone to crack in melting and cooling process. In addition, the oxide film of AZ91-xCa alloy is incompact and cannot inhibit the diffusion of reaction particles. The oxide film of AZ91-xCa alloy turns to thin and plastic one after Y is added, and the density of the oxide film increases greatly due to the formation of composite oxide film composed of MgO, CaO and Y2O3.     

High-temperature oxidation of AZ91-0.3%Ca-0.1%Y alloy in air

AZ91 magnesium alloys containing 0.3% Ca and 0.1% Y were cast, and their oxidation behavior was investigated between 425 and 600 °C in atmospheric air to examine roles of Ca and Y during oxidation. During casting, Ca formed Al₂Ca particles intergranularly, and reduced the amount of Al₁₂Mg₁₇ particles, while most of yttrium existed as Al₂Y particles inter- and intra-granularly in the alloy. The AZ91 alloy oxidized fast above 425 °C, leading to complete ignition. By contrast, AZ91-0.3Ca-0.1Y alloy oxidized very slowly up to 550 °C. Calcium, which is more active than Mg, preferentially oxidized to CaO at the surface of the MgO-rich oxide to suppress the oxidation, evaporation and diffusion of Mg during the initial oxidation stage. Such suppression was due to the quite low vapor pressure and high stoichiometry of CaO. Calcium also suppressed the formation of less oxidation-resistant Al₁₂Mg₁₇ through forming oxidation-resistant Al₂Ca in the alloy from the initial oxidation stage.     

阻燃镁合金的研究现状及进展

综述了阻燃镁合金的研究开发现状,尤其是Ca、Be、Zn和稀土在镁合金中的阻燃作用及其阻燃机理,指出了阻燃镁合金研究目前还存在的问题和今后的研究重点。