Plasma transferred wire arc (PTWA) process was employed to deposit wear resistance coating (approximate 240 μm) on the aluminum engine bore surface. The PTWA coating has a lamellae structure with splats, pores, oxides, and unmelt particles. The volume fraction of porosity was 5.8 %. The coated bore was subjected to non-firing floating-liner test. Cast iron bore was tested for comparison purposes. The friction force of the coated engine bore was recorded lower than that of cast iron engine bore. The surface and cross-sectional microstructural analysis was performed at TDC and mid-stroke after the engine tests. The unworn region (virgin) was analyzed for comparison to determine the wear mechanisms. Abrasive wear and splat delamination contributed the wear of aluminum engine bore with the PTWA coating. Adhesion tests were performed on virgin part. A cohesion strength of 19.51 MPa and a adhesion strength of 29.03 MPa were recorded.
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