【作者】 张玉碧；

【导师】 李照美； 李云东；

【作者基本信息】 河南农业大学 ， 农业机械化工程， 2005， 硕士

【摘要】 课题主要研究了脉冲电沉积法制备纳米晶体镍,并对其在金刚石工具制造方面的应用进行了研究。通过对脉冲电沉积机理及动力学分析,为实验提供了理论基础,通过SEM,XRD分析和相应的力学性能的测定,研究了脉冲参数与其结构性能的关系,证明了沉积层为纳米材料,并以此为基础确定了制造金刚石工具的最佳工艺参数。主要内容和试验结果包括: 1.通过对脉冲电沉积机理和动力学分析,从理论上论述了电沉积的工艺可行性和主要影响因素。 2.通过对脉冲电沉积纳米晶镍沉积层的SEM、XRD分析,从微观角度研究了沉积层的表面形貌、织构和晶粒大小。分析表明,微观形貌为胞状结构,呈(111)晶面择优取向,在脉冲参数为T2-30-100和T2-45-100条件下,平均晶粒尺寸分别为10.3nm和7.6nm,随着占空比的减小,晶粒得以细化。 3.通过对沉积层的显微硬度和拉伸强度的测定和热处理试验表明:最大显微硬度达到591HV,最大拉伸强度大900MPa,分别为常规镍镀层的4和2.5倍;脉冲参数对显微硬度和拉伸强度的影响符合相似的规律,但也有所不同;热处理试验表明各参数条件下的沉积层显微硬度的变化符合相同的规律,说明脉冲参数对沉积层的热稳定性影响不大。 4.通过正交试验方法确定出制造金刚石工具的最佳工艺参数。 5.利用上述工艺方法及参数成功地制造出合格的金刚石工具。更多还原

【Abstract】 This paper studies mainly to prepare nano-crystal nickel layer by pulse electro deposition and researched deeply the application in diamond tool manufacture. Through the dynamic analysis of pulse electro deposition mechanics ,it lies the basis of experiment. Through SEM,XRD and mechanic properties measure the texture structure and properties of nano-nickel layer are analysied and nano-Nickel layer is gotten, and on the basis of these parameters, the optimal parameters is found in manufacture diamond-tool. The main content and experiment results is following. l).Through pulse deposit mechanics and kinetics analysis, the process feasibility and primary influential factors are analysied.2).Through SEM and XRD analysis of pulse electro deposition layer, surface morphology, texture and grain size are studied. The analysis shows that micro-morphology is lumpy structure, appearing to orient prior to （111） crystal plate. Under the condition of T_on = 2ms,T_off =30ms, I_j =100A/dm², the grain size are 10.6nm and 7.6nm respectively. With the cycle duty is decreasing, the grain size is falling. 3).Through the measure of micro-hardness and stretch strength and the heat-treatment experiment, the results show that the biggest micro-hardness and stretch strength amount to 591Hv and 900MPa as 4 and 2.5 times as normal nickel layer respectively. The effect of pulse parameters on micro-hardness and stretch strength correspond to similar law, but different slightly. The heat-treatment experiment shows the change of layer micro-hardness has live up to the same law. This prove that the effect of pulse parameter on heat stability is very small.4).The optimal parameters are gotten by the method of perpendicular experiment. 5).The diamond tools are manufactured successfully using the previous process and parameters.更多还原