Complex Grinding Assisted with Electrical Discharge Machining for Electrically Conductive PCD

Abstract

A new PCD material named EC-PCD (Electrically conductive polycrystalline composite diamond), which consists of electrically conductive diamond grits, has recently been developed. This paper deals with an investigation of a complex grinding assisted with electrical discharge machining (EDM) to realize high efficiency, low and stable grinding force and low wheel wear for the new EC-PCD. The effect of complex grinding assisted with EDM is compared experimentally with the standard PCD (S-PCD). The result shows that, in the complex grinding, lower and more stable grinding force is realized thanks to the material removal action in EDM and that lower wheel wear and better surface finish are attained, just when the EC-PCD is selected as a workpiece.

Effect of Complex Electrodischarge Grinding for Electrically Conductive PCD

“…Until now, they have examined material properties [3] and machinability of the proposed PCD that is EC-PCD (Electrically Conductive PCD). As a result, it has been found that grindability of EC-PCD is similar to that of the existing PCD (C-PCD or conventional PCD) in case of the grinding using surface grinder [4]. On the other hand, examination results on EDM machinability showed that the machining efficiency on EC-PCD was many times higher than on C-PCD [5].…”

Development of a Vitrified Bonded Superabrasive Wheel with Electrical Conductivity and its Application

“…1(a)). The authors have applied this method to the grinding of polycrystalline diamond composite (PCD) and have demonstrated that a stabilized grinding force, a higher grinding ratio and a better surface finish could be attained [6]. In the EDM assisted grinding of PCD (Fig.…”

Electrical discharge machining of polycrystalline diamond: A review

“…It is known that the low electrical conductivity caused by the unconductive diamond grains is the root cause of low EDM machining efficiency. Based on this knowledge, a new electrically conductive PCD, namely ''EC-PCD'' (Figure 12), 102,[104][105][106][107] was developed to improve the machinability of PCD materials. This new PCD material has been applied in several machining fields, such as die/sink EDM, wire-EDM, ultrasonic EDM, and EDG, due to its significant improvements in MRR, EWR, and SR of the EDM process.…”

“…Due to its low resistivity and dense structure, copper electrodes yield better SR than graphite electrodes, 100,101 and this is a convincing example of the copy effect. The properties of the workpiece, such as grain size 55,89 and conductivity 107,120 of the diamond and the distribution of binder material, 121 also influence the EDM machining performance. Flushing pressure and dielectric flow rate are other critical factors that play important roles in affecting the roughness machined surface.…”