Role of Surface Cracking and Recast Layer Deposition …
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Fig. 3 Average recast layer thickness as influenced by peak discharge current (when using Cu
electrode): a RLT = 21.14 µm, b RLT = 32.78 µm, c RLT = 34.37 µm, d RLT = 38.87 µm, e RLT
= 31.28 µm
material removal rate appears lesser because of its lower strength and lower thermal
conductivity [22].
Figure 6 demonstrates results of EDS analysis performed at (a) recast layer and
(b) at an interior location of the parent workpiece (EDMed specimen obtained using
Cu electrode at Ip = 16 A). It is clearly noticed that within the recast layer, carbon
percentage is more due to thermal decomposition of the dielectric medium, resulting
in significant migration of carbon within the recast layer. Carbon enrichment causes
89
Fig. 3 Average recast layer thickness as influenced by peak discharge current (when using Cu
electrode): a RLT = 21.14 µm, b RLT = 32.78 µm, c RLT = 34.37 µm, d RLT = 38.87 µm, e RLT
= 31.28 µm
material removal rate appears lesser because of its lower strength and lower thermal
conductivity [22].
Figure 6 demonstrates results of EDS analysis performed at (a) recast layer and
(b) at an interior location of the parent workpiece (EDMed specimen obtained using
Cu electrode at Ip = 16 A). It is clearly noticed that within the recast layer, carbon
percentage is more due to thermal decomposition of the dielectric medium, resulting
in significant migration of carbon within the recast layer. Carbon enrichment causes