Discharge current effect on machining characteristics and mechanical properties of aluminum alloy 6061 workpiece produced by electric discharging machining process

Surface treatments are normally carried out after machining. Surface treatment is a costly and time-consuming process. Hence, it makes sense to reduce the requirement of surface treatment as much as possible. Electrical Discharge Machining (EDM) is a frequently used machining process. EDM produces a recast layer on the surface of machined components. The tribological performance of this recast layer is not very well understood. The properties of the recast layer formed as a result of EDM depend upon the discharge current, electrodes and dielectrics. This work aims to study the effects of each on the tribological performance – in terms of the wear depth, friction coefficient, friction force and contact surface temperature of recast layers. Subsequent improvement in the quality of surfaces will significantly reduce the cost and time required to treat surfaces after machining. Hence, various combinations of discharge current, dielectrics and electrodes have been used to characterize and deduce their effects. The tribo-tests are performed in the boundary lubrication regime under pin-on-disc configuration to analyze sliding friction, contact surface temperature and the wear of the recast layers formed on AISI 304L. The surface morphology of the test pins has been performed by Scanning Electron Microscopy (SEM) before and after the tests. The results show that indeed it is possible to control the tribological performance of the recast layers by varying EDM parameters. This approach promises to be a useful methodology to improve the tribological performance of the layers formed after EDM and reduce the time and costs required for surface treatments post machining.

show abstract

“…In addition, the thickness of the recast layers had no effect on their hardness. These observations are consistent with the findings in [ 42 ].…”

Section: Resultssupporting

confidence: 94%

Tribological Characterization of Electrical Discharge Machined Surfaces for AISI 304L

et al. 2022

View full text Add to dashboard Cite

show abstract

“…To simplify distinguishing the texture orientation of the samples machined, we define b z as the direction parallel to the axis of extrusion. All samples were machined by electrical discharge machining (EDM) using skim cut settings in order to minimize surface roughness and damage caused by machining [54][55][56]. The AA-1100-O RPRs were then heat-treated at 615 K for 1 h in accordance with ASM standards in order to anneal defects present in the sample [57].…”

Section: Sample Preparationmentioning

confidence: 99%

Determining elastic anisotropy of textured polycrystals using resonant ultrasound spectroscopy

et al. 2021

View full text Add to dashboard Cite

Polycrystalline materials can have complex anisotropic properties depending on their crystallographic texture and crystal structure. In this study, we use resonant ultrasound spectroscopy (RUS) to nondestructively quantify the elastic anisotropy in extruded aluminum alloy 1100-O, an inherently low-anisotropy material. Further, we show that RUS can be used to indirectly provide a description of the material’s texture, which in the present case is found to be transversely isotropic. By determining the entire elastic tensor, we can identify the level and orientation of the anisotropy originated during extrusion. The relative anisotropy of the compressive (c11/c33) and shear (c44/c66) elastic constants is 1.5% ± 0.5% and 5.7% ± 0.5%, respectively, where the elastic constants (five independent elastic constants for transversely isotropic) are those associated with the extrusion axis that defines the symmetry of the texture. These results indicate that the texture is expected to have transversely isotropic symmetry. This finding is confirmed by two additional approaches. First, we confirm elastic constants and the degree of elastic anisotropy by direct sound velocity measurements using ultrasonic pulse echo. Second, neutron diffraction (ND) data confirm the symmetry of the bulk texture consistent with extrusion-induced anisotropy, and polycrystal elasticity simulations using the elastic self-consistent model with input from ND textures and aluminum single-crystal elastic constants render similar levels of polycrystal elastic anisotropy to those measured by RUS. We demonstrate the ability of RUS to detect texture-induced anisotropy in inherently low-anisotropy materials. Therefore, as many other common materials have intrinsically higher elastic anisotropy, this technique should be applicable for similar levels of texture, providing an efficient general diagnostic and characterization tool.

show abstract

“…8 and Kuo et al. 9 have machined Al6061 alloy with EDM process to study the influence on surface integrity (surface roughness, recast layer, surface morphology) and machining rate. However, micro-cracks, lower productivity rate, voids, higher recast layer and poor surface quality, are some of the issues raised by the researcher which limits the application of EDM process at broader manufacturing scale in industries.…”

Section: Introductionmentioning

confidence: 99%

Semi-empirical modeling and optimization of process parameters on overcut during MFAPM-EDM of Al6061 alloy

Rouniyar

Shandilya

2021

Proceedings of the Institution of Mechanical Engineers, Part E:

View full text Add to dashboard Cite

Magnetic field assisted powder mixed electrical discharge machining (MFAPM-EDM) process is a hybrid process machining process which improves the machining characteristics and stability of process using assistive magnetic field and dielectric admixed powder. In this article, study on overcut has been performed on MFAPM-EDM machined Aluminium 6061 alloy. Discharge current, powder concentration, pulse on duration, pulse off duration, and magnetic field strength as process parameters have been varied during experimentation. Box Behnken design approach was employed for experimental design to carry out the experiments. Suitable Semi-empirical model was formulated using dimensional analysis for predicting the overcut. The empirical model developed was also compared with RSM model and was found better in predicting the response. Optimum process parameters for minimal overcut was conducted desirability function approach of RSM. Experimental results divulged discharge current as the most important parameters for overcut as compared to other process parameters on account of higher F-value. Confirmatory experiments revealed good correlation between optimum and experimental results.

show abstract

Discharge current effect on machining characteristics and mechanical properties of aluminum alloy 6061 workpiece produced by electric discharging machining process

Cited by 22 publications

References 18 publications

Tribological Characterization of Electrical Discharge Machined Surfaces for AISI 304L

Tribological Characterization of Electrical Discharge Machined Surfaces for AISI 304L

Determining elastic anisotropy of textured polycrystals using resonant ultrasound spectroscopy

Semi-empirical modeling and optimization of process parameters on overcut during MFAPM-EDM of Al6061 alloy

Contact Info

Product

Resources

About