Process capability and effect size of vacuum extraction shaped tube electrolytic drilling of Inconel alloy for high-performance cooling hole

摘要

Cooling holes are important structures in turbine blades for high-performance aircraft engines. Nickel-based superalloys such as Inconel 718 are widely used in manufacturing turbine blades. However, it is very challenging to manufacture cooling holes in Inconel alloys. Conventional machining process such as electrical discharge machining (EDM) and laser beam machining (LBM) are thermal processes, which lead to recast layer, heat-affected zone, and tensile residual stresses. Electrochemical machining is an alternative to machine cooling holes without thermal damage. This paper focuses on the process capability and effect size of vacuum extraction shaped tube electrolytic drilling (VE-STED) process to manufacture cooling holes of Inconel 718. The effect of key process parameters, i.e., applied voltage, electrolyte concentration, and tool feed rate on process efficiency, form accuracy, and process stability has been investigated. The effect size was determined using ANOVA.