Adnan Muhammad, Qureshi Waqar, Umer Muhammad, Botto Daniele
Mechanical Engineering Department, University of Engineering & Technology Taxila, Taxila 47050, Pakistan.
Mechanical Engineering Department, Institute of Space Technology Islamabad, Islamabad 44000, Pakistan.
Materials (Basel). 2022 Jan 28;15(3):1028. doi: 10.3390/ma15031028.
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.
表面处理通常在机械加工后进行。表面处理是一个成本高昂且耗时的过程。因此，尽可能减少表面处理的需求是有意义的。电火花加工（EDM）是一种常用的加工工艺。电火花加工会在加工部件的表面产生一层重铸层。人们对这一重铸层的摩擦学性能了解并不多。由电火花加工形成的重铸层的性能取决于放电电流、电极和电介质。这项工作旨在研究它们各自对摩擦学性能的影响——从重铸层的磨损深度、摩擦系数、摩擦力和接触表面温度方面进行研究。随后表面质量的提升将显著降低加工后处理表面所需的成本和时间。因此，已采用放电电流、电介质和电极的各种组合来表征并推断它们的影响。摩擦学测试是在销盘配置的边界润滑状态下进行的，以分析AISI 304L上形成的重铸层的滑动摩擦、接触表面温度和磨损情况。测试销的表面形貌在测试前后通过扫描电子显微镜（SEM）进行了观察。结果表明，通过改变电火花加工参数确实有可能控制重铸层的摩擦学性能。这种方法有望成为一种有用的方法，以改善电火花加工后形成的层的摩擦学性能，并减少加工后表面处理所需的时间和成本。
