磁场辅助电火花表面强化技术及实验研究

发布时间：2018-01-08 22:22

本文关键词：磁场辅助电火花表面强化技术及实验研究　出处：《太原理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：随着电火花加工技术的日益成熟，电火花加工的应用范围越来越广，利用其独特的加工原理，电火花加工技术已成功的在表面强化领域得到了应用并取得一定成果。基于电火花沉积理论，本文采用普通D703F电火花高速小孔加工机床，研究了利用它实现工件表面强化的新方法，通过改变机床电极的极性，实现了气中放电表面沉积工艺，在45钢表面沉积了WC强化层。从沉积层的厚度、粗糙度和微观缺陷三个方面分析了工艺参数对沉积层质量的影响，，试验结果表明：采用该设备进行沉积时，当电流脉宽为80μs，强度为7A时，可获得综合质量最优的沉积层，并在此工艺参数下制备了厚为35μm，硬度达1000HV，无明显缺陷的碳化钨沉积层。普通电火花机床加工得到的沉积层厚度较小、表面粗糙度较大，为了解决这个问题，人们做了大量实验研究。为了得到更好的沉积层，提出采用辅助磁场与电火花复合沉积的方法，通过永磁场的作用，使铁磁工件材料被磁化，从而使铁磁材料受到一个向下的磁场力而难以脱离工件表面，这样可以使得沉积层的厚度增大，表面粗糙度降低，材料的利用率提高。采用大电规准进行的表面强化，得到的强化层厚度大,表面粗糙度差。为了得到大的沉积层厚度、小的沉积层表面粗糙度，文本采用了两种优化方案，一是利用大电规准对表面进行加工后，再利用小电规准对该表面进行加工；二是用大电规准对表面进行加工后，利用滚磨设备对其表面进行光整加工。实验结果表明：两种优化方案都能降低大电规准加工得到的表面的粗糙度，同时厚度基本保持不变。
[Abstract]:With the growing maturity of EDM technology, the application of EDM is more and more extensive. With its unique machining principle, EDM technology has been successfully applied in the field of surface strengthening and has made some achievements.
This paper based on the theory of electric spark deposition, using common D703F EDM hole high-speed machining tool, it is studied by using the new method for strengthening surface of workpiece, by changing the polarity of machine tool electrode, the discharge gas in the deposition process, WC coating deposited on the surface of 45 steel. The thickness of the deposited layer, the effect of the process parameters on the deposition layer quality analysis of roughness and micro defects in three aspects, the results show that the use of the equipment for deposition, when the current pulse width is 80 s, the strength of 7A, the deposition layer can be obtained comprehensive optimal quality, based on these parameters to prepare a thick 35 m the hardness of 1000HV, tungsten carbide deposition layer without obvious defects.
Ordinary EDM machining the sedimentary thickness is small, the surface roughness is larger, in order to solve this problem, people have done a lot of experimental research. In order to get a better deposition layer, puts forward a method of magnetic field and EDM Compound deposition, the permanent magnetic field, the ferromagnetic workpiece material is magnetized, thus the ferromagnetic material to the surface of the workpiece by a downward from the magnetic force, it can increase the thickness of the deposited layer, the surface roughness decreased, the material utilization rate is increased.
The EDM surface strengthening of the obtained strengthening layer thickness and poor surface roughness. In order to obtain the sediment thickness of the deposited layer, small surface roughness, the text uses two kinds of optimization schemes, one is to use the electrical parameters of the machined surface, the use of small power the criteria for processing on the surface; two is used to process the surface of EDM, grinding equipment, finishing on the surface. The experimental results show that the two kinds of optimization schemes can reduce the EDM surface roughness obtained at the same time, the thickness of the base remains unchanged.

【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TG661

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