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Al-TiO2-B2O3反应体系中B2O3/TiO2摩尔比对热扩散反应合成铝基复合材料磨损性能的影响 总被引:1,自引:0,他引:1
利用Al-TiO2-B2O3体系热扩散反应合成(XD)法制备了铝基复合材料;采用销-盘摩擦磨损试验机考察了所制备的铝基复合材料在干摩擦条件下同GCr15钢配副时的磨损性能;采用扫描电子显微镜和光学金相显微镜观察分析了复合材料微观组织结构及其磨损表面和剖面形貌,探讨了其磨损机理.结果表明:所制备的铝基复合材料的磨损性能随Al-TiO2-B2O3反应体系中B2O3/TiO2摩尔比的增加而提高;复合材料的磨损质量损失随着滑动速度的增加而增加,当滑动速度为0.9 m/s左右时最大,随后开始减小;磨损质量损失与滑动距离基本呈线性关系.当B2O3/TiO2摩尔比为0.0时,增强相由Al2O3和Al3Ti组成,相应的复合材料的抗磨性能较差,其磨损主要表现为Al3Ti的犁沟切削、亚表层剥落、塑性基体流失导致Al2O3颗粒裸露脱落以及Al3Ti棒断裂导致的磨粒磨损;加入B2O3后,棒状Al3Ti的数量减少,有利于基体晶粒细化,提高复合材料强度和塑性,故抗磨性能提高.当B2O3/TiO2摩尔比为1.0时,复合材料中的Al3Ti基本消失,抗磨性能显著改善,主要磨损机制为粘着磨损和轻微磨粒磨损. 相似文献
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Al-TiO2系XD合成Al3Ti的形貌及其影响因素分析 总被引:1,自引:0,他引:1
本文主要研究了Al-TiO2系XD合成铝基复合材料的反应产物Al3Ti的形貌及其演变的影响因素.研究表明Al-TiO2系反应产物由Al2O3和Al3Ti组成,Al2O3为细小颗粒,与铝液不润湿,偏聚于基体颗粒的界面;Al3Ti呈棒状,优先生长方向为<110>;随着增强相体积分数的增加,反应温度提高,活性Ti原子的扩散能力增强,扩散路程变短,有利于Al3Ti择优生长,但Al2O3颗粒的浓度增加,使Ti原子的扩散阻力和Al3Ti的生长阻力同步增大,Al3Ti的择优生长倾向反而减弱,其形貌由棒状向块状演变;在纯铝液中Al3Ti的生长形貌为细长棒状,而在真空中则为薄片状;随着保温时间的延长,其轴向尺寸明显增大,径向尺寸增加不明显. 相似文献
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硅酸铝短纤维对其增强ZL109复合材料磨擦因数影响的双重性 总被引:1,自引:2,他引:1
采用预制件液态模锻法制备了硅酸铝短纤维增强的ZL109复合材料,并以合金球墨铸铁为偶件,在干摩条件下于MG-2000高速高温摩擦磨损试验机上,对复合材料的摩擦性能进行了试验研究,考察了硅酸铝短纤维的添加量对这种材料摩擦因数的影响。结果表明,随着纤维添加量(以体积分数计)由0.0%增至7.0%,复合材料摩擦因数的变化是先降低而后升高,纤维添加量为4.5%时的摩擦因数呈现出最低值,而纤维添加量为7.0 相似文献
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纳米CuO的形貌控制合成及其性能研究 总被引:16,自引:0,他引:16
The CuO nanocrystals were prepared by quick-precipitation and hydrolysis method respectively, using Cu(Ac)2 and NaOH as starting materials. The as-prepared CuO nanocrystals were characterized by XRD, TEM, XPS, UV-Visible absorption spectroscopy and BET. The catalysis of CuO nanocrystals of different morphologies on ammonium perchlorate decomposition was investigated by thermal analysis. Results indicated the variation in temperature for NaOH addition played an important role in the shape of the CuO nanocrystals in precipitation method. Well-dispersed spherical CuO nanocrystals with an average size of 6 nm could be obtained when NaOH was added at 100 ℃ and spindle-shaped CuO nanocrystals exceeding 100 nm in diameter were obtained when NaOH was added at room temperature. Needle-shaped CuO nanocrystals could be prepared by the hydrolysis method, and the presence of small amounts of cetyltrimethylammonium bromide (CTAB) could make needle-shaped CuO well dispersed. The catalytic activity of CuO nanocrystals of different morphologies on ammonium perchlorate decomposition was high. The 2% of spherical CuO nanocrystals could make higher decomposition temperature of ammonium perchlorate decreased to 102 ℃. The exothermic quantity of decomposition was from 590 J·g-1 up to 1 420 J·g-1. 相似文献
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采用预制件液态模锻法制备了硅酸铝短纤维增强的ZL109复合材料,并以合金球墨铸铁为偶件,在干摩条件下于MG-2000高速高温摩擦磨损试验机上,对复合材料的摩擦性能进行了试验研究,考察了硅酸铝短纤维的添加量对这种材料摩擦因数的影响.结果表明,随着纤维添加量(以体积分数计)由0.0%增至7.0%,复合材料摩擦因数的变化是先降低而后升高,纤维添加量为4.5%时的摩擦因数呈现出最低值,而纤维添加量为7.0%时复合材料的摩擦因数与基体的基本相当.在用扫描电子显微镜对磨损表面形貌观察的基础上,着重讨论了硅酸铝短纤维对复合材料摩擦因数影响的双重性,指出这种双重性影响导致纤维含量较低时,纤维分布于磨损表面有利于复合材料摩擦因数的降低,而当纤维含量较高时则使复合材料的摩擦因数升高. 相似文献
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