Surface modification of Al-7075 using Cu-CNT green tool in EDM

Abstract

Now-a-days carbon nanotube (CNT) is widely used because of its inimitable properties such as high electrical and thermal conductivities, high tensile strength, etc. In this work, an attempt has been made to modify the surface of Al-7075 alloy using Cu-MWCNT powder metallurgy green compact tool in the electric discharge machining process. The effects of contributing parameters i.e. peak current (I p ), voltage and compact load (CL) have been investigated with respect to performance measures such as, Material Deposition Rate (MDR), Tool Wear Rate (TWR) and Surface Roughness (Ra). The modified surface has been assessed by optical microscopy, FESEM, XRD and EDS analyses. Highest MDR of 0.15 mg min -1 , lowest TWR of 2.05 mg min -1 and lowest Ra of 2.57 µm have been attained. The deposition of tool materials has improved the microhardness up to 2.6 times than that of base material.

Parametric study on surface modification of Al-7075 alloy using electric discharge coating

“…Aluminium 7075-grade plate measuring 25 mm×18 mm with a thickness of 2.5 mm has been selected as the substrate material in this investigation owing to its properties such as low weight, high tensile strength, etc. 6 Table 1 presents the chemical composition of Al-7075 with T0 heat treatment conditions. Micron-sized copper particles with a mesh size of 325 have been selected as the binder material, and MWCNT with a tube diameter of 5-10 nm has been selected as the primary material for the surface modification process.…”

“…The PM green compact tool has been prepared by mixing the powders of Cu and MWCNT in specific weight percentages by following the available literature. 6,25 The surface area to volume ratio of nanoparticles is comparatively high with respect to the microparticles. Due to this, the ratio of weight percentage of Cu micro-powders and MWCNT particles is maintained at 98:2.…”

“…The process of material transfer using EDM can be achieved by two established techniques: Deposition using powder metallurgical (PM) tooling and deposition involving powder mixed dielectric. 6 Though both processes have an impact in the field of EDM deposition but studies have shown that the PM tool offers precise control over the distribution of particles, ensuring uniformity in deposition. 7 Previous research has reported the effective deposition of materials such as silicon carbide, 8 titanium di-boride, 9 tungsten carbide, 10 MWCNT, 6 copper-nickel, 11 tungsten, 12 tungsten disulphide, 13,14 hexagonal boron nitride, 4 molybdenum disulphide, 15 etc.…”

Experimental analysis of surface integrity in electro-discharge coating process

“…The deposition process exhibited minimal crack formation, achieved excellent metallurgical bonding and resulted in high hardness (around 1059 HV0.3) and superior wear resistance. Barua and Rahang 13 utilised a Cu-MWCNT green compact to enhance the Al-7075 surface and investigated the impact of I p , V and CL on material deposition rate (MDR), tool wear rate (TWR) and Ra. They achieved a significant improvement in MH reaching up to 2.6 times higher than the original material through the deposition of tool materials.…”

Surface modification in the shape of a pattern using crepe paper maskant in EDM

“…They investigated the machining parameters that influence the coated surface's surface integrity and tribological properties. Barua and Rahang [7] applied Cu-MWCNT PM tool in EDM to alter the surface of the Al-7075 and improved the hardness up to 2.6 times compared to the base material. By PM tool (green compact of tungsten and copper), Mazarbhuiya et al [8] altered the surface of CFRP composite materials in EDM.…”