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排序方式: 共有386条查询结果,搜索用时 218 毫秒
281.
282.
Al—Li合金表面的化学镀镍 总被引:2,自引:0,他引:2
介绍了Al-Li合金表面化学镀镍的工艺方法,镀层结合力测试以及孔隙率、氯化钠浸泡试验表明,化学镀镍层可能成为Al-Li合金这一新型航空航天材料的良好防护层。 相似文献
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氢化锂含氚量的实际及化与氚的自然衰变规律并不完全一致,为了测定其变化规律,对贮存中的氢化锂含氚量进行了长时间跟踪测量。本文利用实测数据与多项式回归法,结合氚的衰变规律建立了氢化锂含氚量变化的数学模型,此模型在测量点具有很低的预测误差。 相似文献
285.
张志力 《南昌航空工业学院学报》1998,(4):70-73
本文介绍了一种新型的制备氧化物涂层的新方法,溶胶-凝胶法,较详细地介绍了用该方法制备二氧化铈,二氧化钛,二氧化硅,二氧化锆,镧系稀土氧化物等涂层的原理,方法及用途。 相似文献
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287.
JING Rui-rui LIU Fu-shun 《中国航空学报》2007,20(2):153-156
The influences of Co-addition on phase transformation behavior and mechanical properties of TiNi alloys were investigated. Re- sults indicate that, as a substitute for Ni, Co added to TiNi alloys can dramatically decrease the martensite transformation temperature, and R phase transformation and martensite transformation are accordingly separated. When Co-content reach 10 at.%, the martensite transformation temperature is lower than that of liquid nitrogen. During deformation at room temperature, Ti50Ni48Co2 alloy exhibits good ductility with a lower stress plateau caused by stress-induced martensite and martensite reorientation. 相似文献
288.
TANG Mao-yu JI Tian-hao XIE Jian 《中国航空学报》2007,20(2):177-180
SrTiO3 submicro-wires were prepared by the reaction of layered titanate nanowires with Sr(OH)2 powder in an autoclave. The wires were investigated using X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), Ultra-violet visible (UV-vis), photoluminescence (PL) and Raman spectroscopy. The XRD measurement shows that the prepared SrTiO3 submicro-wires hardly have impurity phases. The SEM and TEM images demonstrate that the scalable wires, which need to be proc- essed at the reaction temperature of 180 ℃ for about 48 hours, are not composed of single crystals. The PL shows that the wire-like SrTiO3 has emission peaks at the wavelengths of 568 and 585 nm. Further, the Raman spectroscopy reveals structural changes in the products through different reaction time. 相似文献
289.
Effects of RRA Treatments on Microstructures and Properties of a New High-strength Aluminum-Lithium Alloy-2A97 总被引:1,自引:0,他引:1
YUAN Zhi-shan LU Zheng XIE You-hua DAI Sheng-long LIU Chang-sheng 《中国航空学报》2007,20(2):187-192
A new high strength 2A97 Al-Cu-Li-X alloy was subjected to triple-aging of retrogression and re-aging treatments (RRA). Transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and tensile tests were used to investigate the effects of RRA treatment on the microstructures and properties. DSC test reveals the reversion temperature range of the strengthening δ' (Al3Li)phase. The results show that the microstructure consists of δ' (Al3Li) phase, T1 (Al2CuLi) phase and θ"/θ'(Al2Cu) phase for 2A97 alloy treated by a triple-aging ora retrogression and re-aging treatment in the following order: (1) at 165 ℃×30 min, (2) at 220 ℃ or 240 ℃×15 min, (3) at 165 ℃×24 h. The plastic deformation, incorporated into the treatment after secondary high temperature aging, promotes the T1 precipitation during final re-aging. The tensile properties of the alloy treated by the retrogression and re-aging treatment reach the peak level of alloy single-aged at 165 ℃ in T6 temper. 相似文献
290.