Role of Multi-Wall Carbon Nanotubes on the main parameters of the Electrical Discharge Machining (EDM) process

Electrical discharge machining is a very accurate non-traditional manufacturing process for creating tiny apertures, complex shapes and geometries within mechanical parts and assemblies. Its performance is evaluated in terms of surface roughness, existence of cracks, voids and recast layer on the surface of product. The high heat generated on the electrically discharged material during the EDM process unfortunately decreases the quality of product. In this paper the high strength and unique electrical and thermal properties of multi-wall carbon nanotubes are used to improve the EDM performance when machining the AISI H13 tool steel, by means of copper electrodes. Material removal rate, electrode wear rate, surface roughness and recast layer were measured in presence of carbon nanotubes in the dielectric, then compared to the outcome of traditional EDM. Experiments show that mixing multi-wall carbon nanotubes within the dielectric makes the EDM more efficient, particularly if machining parameters are set at low pulse of energ

Mechanically assisted electrochemical degradation of alumina-TiC composites

Alumina-TiC composite material is a tough ceramic composite with excellent hardness, wear resistance and oxidation resistance in dry and high-temperature conditions. In aqueous conditions, however, it is likely to be electrochemically active facilitating charge transfer processes due to the conductive nature of TiC. For application as an orthopedic biomaterial, it is crucial to assess the electrochemical behavior of this composite, especially under a combined mechanical and electrochemical environment. In this study, we examined the mechanically assisted electrochemical performance of alumina-TiC composite in an aqueous environment. The spontaneous electrochemical response to brushing abrasion was measured. Changes in the magnitude of electrochemical current with abrasion test conditions and possible causal relationship to the alteration in surface morphology were examined. Results showed that the alumina matrix underwent abrasive wear with evidence of microploughing and grain boundary damage. Chemical analysis revealed TiO2 formation in the abraded region, indicating oxidation of the conductive TiC domain. Furthermore, wear debris from alumina abrasion appeared to affect reaction kinetics at the composite-electrolyte interface. From this work, we established that the composite undergoes abrasion assisted electrochemical degradation even in gentle abrasive conditions and the severity of degradation is related to temperature and conditions of test environment

High cycle fatigue of electrical-discharge machined AISI D2 tool steel

[[abstract]]An analysis of electrical-discharge machined AISI D2 tool steel for high-cycle fatigue is conducted. The damage model was developed to reveal the influence of different electrical-discharge machining conditions on the fatigue life. The processed surface layer and the cross-section were examined by scanning electron microscopy (SEM). The experimental results show that the fatigue life of the EDMed specimens is shorter than the mechanically polished samples. These results can be attributed to the micro damage in the resolidified surface layer produced by EDM. The effect of the magnitude of the pulse current on the fatigue Me of the specimen is more significant than the pulse on-time. The predicted results agree fairly with the experimental results.[[fileno]]2020212010039[[department]]動機

Recycled Ti-17 Based Composite Design; Optimization Process Parameters in Wire Cut Electrical Discharge Machining (WEDM)

International audienc