Degradation of NiCr/CuNiMn/NiCr films on alumina substrates

This paper addresses the aging behaviour of NiCr/CuNiMn/NiCr triple layers on Al₂O₃ ceramics at temperatures up to 200°C for film thicknesses d0.5 μm. Investigations of the film structure and the increase of resistance and its temperature coefficient during the annealing process and studies of the dependence of this aging drift on both the film thickness and the storage temperature have been carried out. Furthermore, the film stress and the effect of substrate bending on resistance have been measured. The results can be explained by the irregular film structure (columns and small bridges between them), which causes stress and current concentrations as well as local creeping, cracking and oxidation processes in the micro-bridges. They are compared with such for structurally homogeneous films on silicon wafers.     

节能型铝合金连续熔化－去气炉

介绍一种用于铝合金的连续熔化－去气的节能装置。着重讨论了此装置的结构和操作要点以及影响铝合金质量的因素。文中对比了此装置与传统阶段式熔化系统操作上的异同点。分析了连续熔化炉的经济效益。研究表明毛坯耗电量下降８５％，并可减少合金元素加入量以及坩埚和加热元件的消耗。铸件质量合格。     

记第二届环太平洋先进材料及工艺国际会议

介绍第二届环太平洋先进材料及工艺国际会议情况，重点报导韩国钢铁工业、早期凝固过程研究、喷射成形、非晶合金、纳米材料和第三代单晶铸造高温合金等内容。     

Synthesis and characterization of mechanical-alloyed Ti–xMg alloys

The synthesis and characterization of Ti–xMg (x=4, 9, 12, 15, 21, 24 at%) alloys using mechanical alloying was investigated. A nanometer-sized Ti–24Mg alloy was produced. During mechanical alloying, the height of the XRD peaks of the Mg in the Ti–9Mg alloy decreased, and then disappeared, whereas the Ti XRD peaks broadened, and the grain size decreased with increasing milling time. The Mg firstly dissolved in the grain boundaries of the Ti, and then diffused into the Ti grain interiors. The grain boundaries played an important role in enhancing the solid solubility of Mg in Ti. With increasing Mg content the volume fraction of grain boundaries increased, and a decrease in grain size occurred after mechanical alloying for 48 h.     

用二元固溶体取代多元固溶体制取硬质合金的研究

固溶体是生产钛钨钴硬质含金的一种重要原料，其质量对硬质含金的性能影响极大。为此，本文作者对TiC－WC复式磁化物的成分、亚结构与性能进行了大量的研究并进行了用二元固溶体（TiC－WC）取代多元固溶体制取YS30和YM052硬质合金的研究。通过对固溶体添加方式、氢气中碳化的固溶体（TiC：WC＝50：50）与真空中脱气处理后的固溶体对比试验、不同的脱错和烧结工艺条件试验以及切削试验，证明用二元固溶体取代多元固溶体是可行的．用其制取的YS30和YM052硬质合金的性能和使用效果已达到或超过了原工艺生产的YS30和YM052合金的性能和使用效果。     

铸造亚共晶铝硅合金绿色化规划探讨

根据绿色化思想，对铸造亚共晶铝硅合金进行了绿色化规划探讨。现有的铝硅合金牌号过多，以铸造亚共晶铝硅合金为例，中国至少有11种牌号，美国有14种，俄罗斯有16种，日本有11种。同时，这些合金的性能大多相互覆盖。这为材料选择，加工，管理和回收带来诸多不便。为了解决这些问题，规划出两种牌号，足以满足一般的要求，一种为低成本，中等性能合金（σb=150-200MPa,δ5＝1.0%-4.0%，如美国的356．0或中国的ZL101）；另一种为中等成本，中高性能合金（σ＝200－420MPa,δ5=2.0%-8.05,如我国新近开发的ZL120）。     

镁系储氢合金的表面处理

根据国内外有关对Mg系储氢合金表面改性的研究结果 ,综述了近年来Mg系储氢合金的几种表面处理方法 ,以及对MH电极的电化学性能的影响 ,认为氟处理是今后研究发展的重点和方向。