Micallef, ChristianZhuk, YuriAria, Adrianus Indrat2022-09-162022-09-162022-09-09Micallef C, Zhuk Y, Aria AI. (2022) Surface finishing and tool wear in single point diamond turning of chemical vapour deposited tungsten carbide hard coatings. Surface and Coatings Technology, Volume 447, October 2022, Article number 1288640257-8972https://doi.org/10.1016/j.surfcoat.2022.128864https://dspace.lib.cranfield.ac.uk/handle/1826/18456Precision-engineered components which operate in demanding conditions often require the application of hard coatings such as tungsten carbide (WC) to improve their functional properties. Following the coating deposition process, a surface finishing or machining operation is often required to correct the sizing or achieve adherence to geometrical tolerancing and surface finish requirements. Single point diamond turning (SPDT) is a widely used ultraprecision machining technique for the fabrication of high-end engineering components made up of ductile materials, making it a desirable technique as a post-coating machining or finishing process. In this study the machinability of hard CVD W/WC coatings with a hardness of 1120 ± 15 HV and a thickness of 100 μm using SPDT was investigated. Here we report the results of axial and transverse turning using a cutting speed of 600 rpm and feed rates of 1 and 5 μm respectively. Experimental results show that an Ra of 0.2 μm is achieved with a diamond tool having a 0.5 mm nose radius. Significant tool wear was observed at the rake/flank edge of the diamond tool due to the coating's hardness. Surface and cross-sectional analysis of the samples' machined areas revealed presence of adhesive and abrasive wear. The occurrence of material pile-up due to tool loading on the surface of the coating was investigated through the indentation technique which demonstrated the occurrence of material deformation contributing to the overall surface roughness.enAttribution 4.0 InternationalDiamond turningSPDTTungsten carbideTool wearPlastic side-flowArticle