Investigation of material removal in inner-jet electrochemical grinding of GH4169 alloy.

Electrochemical grinding (ECG) is a low-cost and highly efficient process for application to difficult-to-machine materials. In this process, the electrolyte supply mode directly affects machining stability and efficiency. This paper proposes a flow channel structure for an abrasive tool to be used for inner-jet ECG of GH4169 alloy. The tool is based on a dead-end tube with electrolyte outlet holes located in the sidewall. The diameter and number of outlet holes are determined through numerical simulation with the aim of achieving uniform electrolyte flow in the inter-electrode gap. Experiments show that the maximum feed rate and material removal rate are both improved by increasing the diamond grain size, applied voltage, electrolyte temperature and pressure. For a machining depth of 3 mm in a single pass, a feed rate of 2.4 mm min is achieved experimentally. At this feed rate and machining depth, a sample is produced along a feed path under computer numerical control, with the feed direction changing four times. Inner-jet ECG with the proposed abrasive tool shows good efficiency and flexibility for processing hard-to-cut metals with a large removal depth.