Machining of Zircaloy-2 using progressive tool design in EDM

Abstract

ABSTRACT Zircaloy-2 is used in nuclear and biomedical industries therefore required high accuracy and precision, and achieved by application of electrical discharge machine (EDM). In this study, a new horizon of tool design is investigated for improvement in the performance of EDM. To measure the effect of tool design, Zircaloy-2 is machined with EDM using progressive Cu tool and measured the response parameters (MRR, TWR, radial overcut (Roc ), radial undercut (Ruc ), taper angle (Φ), and surface roughness). The progressive tool with varying design parameters of rake angle (0°, 45°, and 60°), flat land (2 mm), trunk diameters (10, 8, and 6 mm), and relief angle (0°, 45°, and 60°) are used to perform rough and finish machining in single EDM operation. MRR and SR are increased with increase in rake angle due to reduction in oxide and carbide deposition on the machined surface. Best combination for maximum MRR (1.131 × 10−3 mm3/min), minimum SR (4.313 µm), and minimum taper angle (2.17°) is obtained when machining is performed using T7. Multiresponse optimization (R-method) gives highest rank to progressive tool T7. Tool design improved TWR and significant reduction in radial overcut over conventional tool.