This paper presents the experimental investigation on cutting of thin carbon fiber-reinforced polymer (CFRP) composite plate by wire electrical-discharge machining (WEDM) with the aid of sandwich assisting-electrodes. The difficulties such as incomplete cut and deviation in machining path during WEDM of CFRP were avoided by using metal plates (H13 steel) as assisting-electrodes. The spark initiation during WEDM of CFRP is difficult without exposing the carbon fiber as fibers are embedded into nonconductive polymer in CFRP. Thus, in this work, assisting-electrode was used to initiate the sparking without changing the surface integrity of the CFRP. The one-factor-at-a-time analysis was applied to study the effect of input parameters namely input current (2, 4, 6, 8, 10, and 12 A), pulse on time (10, 20, 30, 40, 50, and 60 µs), pulse off time (10, 20, 30, 40, 50, and 60 µs), and voltage (70 and 90 V) on the cutting time and the machined surface morphology. A decreasing trend was observed for cutting time with an increase in the current. Whereas, the cutting time was increased with an increase in the pulse off time. It was also observed that the cutting time initially increased with the pulse on time (10 to 30 µs) and then started decreasing with a further increase in the pulse on time (40 to 60 µs). The cutting time was significantly reduced at a higher level of voltage (90 V) when compared one-on-one with lower voltage level (70 V). In this study, microscopic analysis of the surface morphology was also extensively investigated which was not investigated earlier. The investigation showed damages such as breakage of carbon fibers, fiber-matrix debonding, and matrix cracking during WEDM of CFRP using sandwich assisting-electrode.

本文介绍了在夹层辅助电极的作用下，通过丝线放电加工（WEDM）切割薄碳纤维增强聚合物（CFRP）复合板的实验研究。通过使用金属板（H13钢）作为辅助电极，避免了CFRP电火花线切割过程中切割不完全和加工路径偏离等难题。如果不将碳纤维暴露在CFRP的WEDM中，则很难在未暴露碳纤维的情况下引发火花。因此，在这项工作中，在不改变CFRP的表面完整性的情况下，使用了辅助电极来引发火花。一次单因素分析用于研究输入参数（即输入电流（2、4、6、8、10和12 A），脉冲对时间（10、20、30、40）的影响，50和60 µs），脉冲关闭时间（10、20，30、40、50和60 µs），电压（70和90 V）取决于切割时间和加工后的表面形态。随着电流的增加，切割时间减少了。然而，切割时间随着脉冲关闭时间的增加而增加。还可以观察到，切割时间最初随着脉冲开启时间（10至30 µs）而增加，然后随着脉冲开启时间的进一步增加（40至60 µs）而开始减少。当与较低的电压水平（70 V）一对一比较时，在较高的电压水平（90 V）时切割时间显着减少。在这项研究中，对表面形态的微观分析也得到了广泛的研究，而这是先前没有研究的。调查表明，损坏的原因包括碳纤维断裂，纤维基质脱粘，