Densification and Conolidation of Powders by Equal Channel Angular Pressing
Densification and Conolidation of Powders by Equal Channel Angular Pressing
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等通道角压制粉末的致密化和固结
DOI：
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发表时间：
2007
期刊：
影响因子：
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通讯作者：
Hyoung
中科院分区：
文献类型：
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作者：
S. Yoon;S. Hong;S. Hong;Hyoung
本研究将自下而上的粉末加工方法与自上而下的SPD（剧烈塑性变形）方法相结合，以最小的晶粒生长实现金属粉末的全密度和晶粒细化，这是采用传统粉末冶金方法压实烧结的自下而上方法的瓶颈。采用等通道角压法（ECAP）进行粉末固结，是SPD中最有前途的方法之一。在固体金属和粉末金属的ECAP过程中，了解密度、内应力、应变和应变率分布是非常重要的。采用实验方法研究了金属粉末在ECAP过程中的固结、塑性变形和微观组织演化行为。结果表明，气雾化铝硅粉在ECAP过程中，由于粉末接触面结合良好，可以有效地获得较高的机械强度。实验结果表明，粉末的SPD处理是实现全密度和纳米结构材料的可行方法。
In this study, bottom-up type powder processing and top-down type SPD (severe plastic deformation) approaches were combined in order to achieve both full density and grain refinement of metallic powders with least grain growth, which is considered as a bottle neck of the bottom-up method that uses the conventional powder metallurgy of compaction and sintering. ECAP (Equal channel angular pressing), one of the most promising method in SPD, was used for the powder consolidation. In the ECAP process of not only solid but also powder metals, it is important to get a good understanding of the density as well as internal stress, strain and strain rate distribution. We investigated the consolidation, plastic deformation and microstructure evolution behavior of the metallic powders during ECAP using an experimental method. It was found that high mechanical strength could be achieved effectively due to the well bonded powder contact surface during ECAP process of gas atomized Al-Si powders. The experimental results show that SPD processing of powders is a viable method to achieve both fully density and nanostructured materials.