摘要
利用SEM分析纯镍电铸层,以及用直流和脉冲工艺所制备纳米复合电铸层的表面形貌,测定常温下和经过不同温度热处理后纳米复合电铸层的显微硬度,探讨纳米复合电铸层的强化机理。结果表明,纳米复合电铸层的表面形貌不同于纯镍铸层,并且其显微硬度明显提高。纳米复合电铸层的强化机理主要是细晶强化机制、弥散强化机制和高密度位错强化机制。由于再强化效应的作用,经过热处理后的纳米复合电铸层,尤其是由脉冲电沉积所得纳米复合电铸层,其显微硬度的提高程度尤为明显。
SEM was used for the examination of surface morphology of pure Ni electroforming deposits and the nano-composite electroforming deposits prepared under direct current and pulse current. The micro-hardness of nano-composite electroforming deposits was measured at room temperature and after various heat treatments. The strengthening mechanism was discussed. The results indicate that surface morphology of the nano-composite electroforming deposits is different from pure Ni electroforming deposits, and the micro-hardness of nano-composite electroforming deposits increases. The strengthening mechanisms of the nano-composite electroforming deposits mainly involve fine-crystal effect, nano-particle dispersion effect and dislocation effect. The micro-hardness of heat treated nano-composite electroforming deposits prepared under pulse current is markedly increased owing to the re-strengthening effect.
出处
《铸造》
CAS
CSCD
北大核心
2009年第5期436-439,共4页
Foundry
基金
江苏省自然科学基金重点资助项目(BK2004005)
国防基础研究基金资助项目(J1500E002)
关键词
复合电铸层
显微硬度
强化机理
热处理
再强化效应
nano-composite electroforming deposits
micro-hardness
strengthening mechanism
heat treatment
re-strengthening effect