【摘要】 研究了铝熔体内的原位反应Ａｌ＋ＣｕＯ工艺对反应诱导时间、剧烈程度及产物分布的影响,结果表明随着稀释剂Ａｌ量的增多．熔体内自蔓燃反应启动越慢,剧烈程度降低,反应产物的分布朝不均匀方向变化;熔体的温度越高,反应启动得越快、越剧烈;引发剂镁粉的添加极大地缩短反应诱导时间．制备了原位Ａｌ２Ｏ３颗粒强化含不同产物Ｃｕ的铝基复合材料、ＳＥＭ观察表明铸造条件下Ａｌ２Ｏ３颗粒小于０．５μｍ,均匀地分布在材料的各种基体相上:随着Ａｌ２Ｏ３颗粒的增多．产物Ｃｕ以网状化合物形式分布,拉伸实验显示材料的塑性很低．为降低Ｃｕ量．在原反应物中混合入ＳｉＯ２粉．或采用喷射沉积快速凝固法细化组织,提高固溶量．ＳＥＭ显示网状相得到了细化和均匀分布．拉伸实验表明强度和塑性有大幅度提高．更多还原

【Abstract】 In situ reaction between Al and CuO powder was introduced into pure Al melt to fabricate in situ Al2O3 particles reinforced Al-Cu based composites. Several factors had been studied to determine their effects on the reaction, i.e., ratio of Al and CuO, temperature of the melt and ignition additive Mg on the incubation period, intensity of the reaction and the distribution of the product. It was found that when the amount of Al in the reaction compact is high, and also the temperature of the melt and more Mg additive, the reaction is more violent, the period became shorter and product s dispersion showed more uniform. SEM observation showed that in situ A12O3 particles were less than 0.5 μm in diameter and dispersed in the matrix uniformly. When more Al2O3 particles were produced, more Cu is produced at the same time, which existed as net like brittle phase. The first way to avoid too much Cu was adding SiO2 into the reactants that would result in combined in situ alloying and in situ particle strengthened Al composites. When SiO2 was used as one rcactant apart from CuO, element Cu (less than in Al-Cu matrix) and Si was released into the matrix while remain the same level of Al2O3 particles as that which had high level of Cu in Al-Cu matrix composites. The microstructure was optimized. The second way to reduce the deteriorative effect of high level Cu was utilizing rapid-solidification technology such as spray-deposition technology. The net-like phase had been demolished and became particulates in the matrix. The properties were improved greatly.更多还原