（毕业设计论文）《GCr15钢表面脉冲电沉积Ni-W-P工艺研究》.doc

PAGE X PAGE X 南 京 工 程 学 院 毕业设计说明书(论文) 作 者： 学 号： 学院（系、部）： 材料工程学院 专 业： 金属材料与工程 题 目： GCr15钢表面脉冲电沉积Ni-W-P工艺研究 指导者： 评阅者： 2011年 6 月 南 京 毕业设计说明书（论文）中文摘要 GCr15钢表面脉冲电沉积Ni-W-P工艺研究 在Ni-P二元合金镀层中引入W元素，由于镀层得到弥散强化与固溶强化的双重作用，可提高镀层的硬度和其他性能。因此近年来 Ni-W-P合金镀层得到广泛的研究和应用。本文应用单向脉冲电沉积技术，在GCr15轴承钢基体上制备了Ni-W-P合金镀层。通过电镀工艺对比，研究了电流密度、脉冲频率、占空比对镀层硬度和耐蚀性的影响。用扫描电镜(SEM)研究了镀层的成分和表面形貌。得出最佳的工艺条件是电流密度为4A/dm2、脉冲频率为250Hz、占空比为30%。此时镀层最致密，显微硬度最高，耐蚀性最好，晶粒尺寸最小，表面光亮效果最好。 关键词：脉冲电沉积；Ni-W-P；工艺；性能 毕业设计说明书（论文）外文摘要 Title Process of Pulse Electrodeposition Ni-W-P Alloy on GCr15 Steel Abstract: Introduction of W coating elements in the Ni-P binary alloy can increase the hardness and other performance due to coating by dispersion strengthening and solid solution strengthening,Therefore, in recent years, Ni-WP alloy coating has been widely studied and applied.The Ni-W-P alloy coating on the GCr15 steel was prepared by using nickel sulphate system and one-way pulse electro-deposition. The influence of current density,pulse frequency and duty cycle on the hardness and corrosion resistance of the coating were researched. The structure and surface morphology of the coating were studied by scanning electron microscopy (SEM).The results show that optimum process conditions which is 4A/dm2 current density,250Hz pulse frequency,30% duty cycle.It turns out to be the most densy layer, the highest hardness,the best corrosion resistance, the smallest grain size and the brightest surface at this point . Keywords: Pulse Electrodeposition; Ni-W-P; Process ; Property 目 录 TOC \o 1-3 \h \z \u HYPERLINK \l _Toc13795 前 言 PAGEREF _Toc13795 1 HYPERLINK \l _Toc19177 第一章 绪论 PAGEREF _Toc19177 2 HYPERLINK \l _Toc19097 1.1合金电沉积 PAGEREF _Toc19097 2 HYPERLINK \l _Toc12657 1.1.1电沉积液的组成 PAGERE