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2006年08月02日

【期刊论文】Direct fractographic and microstructural evaluation of different zones within welded dissimilar steel joints

潘春旭， C. Pan*，

Materials Science and Technology 2005 VOL 21 NO6，-0001，（）：

-1年11月30日

Fractographic and microstructural evaluations of fracture surfaces of different zones within welded dissimilar steel joints are difficult to conduct by conventional methods because of the very small dimensions of the various regions in the joint. In the present paper, a novel non-standard notch impact specimen is introduced. By using this specimen, a cross-sectioned fracture was obtained, and successive variations of the fracture surfaces, corresponding to individual microstructures of all regions in the joint, were clearly identified. When comparing the fracture surface between as welded and post-weld heat treated (PWHT) joints, it was found that the transition zone fractured in a brittle disbonding manner owing to carbon migration, and the location of the poorest part in the joints transferred from the heat affected zone (HAZ) in the as welded state into the transition zone after post-weld heat treatment. The described specimen and analysis approach can be used to conduct other fractographic and microstructural evaluations, such as in tensile tests.

Dissimilar steel welding,， Fractography,， Microstructure,， Electron microscopy

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2006年08月02日

【期刊论文】脉冲电镀镍纳米晶基板上碳纳米管和碳纳米纤维的火焰法合成①

潘春旭，刘曰利，

中国有色金属学报，2004，14（6）：980～984，-0001，（）：

-1年11月30日

摘要

提出了一种利用脉冲电镀法在金属基板表面沉积一层具有催化活性的镍纳米晶，再将该基板放入乙醇火焰中合成碳纳米管（CNTs）和碳纳米纤维（CNFs）的方法。利用光学显微镜和X射线衍射仪（XRD）表征了镀层镍纳米晶的形貌和晶格特征，利用透射电镜（TEM）表征了碳纳米管的微观结构。实验研究了基板材料和电镀时间等因素对碳纳米管和碳纳米纤维合成的影响；初步讨论了其生长机理。

脉冲电镀，纳米晶镍，碳纳米管，碳纳米纤维，火焰