Fig. 1 Representative SEM morphologies of SiC particles. a Low magnification, b high magnification

Fig. 2 Representative surface morphologies of 65 vol% SiCp/2024Al composite after a polishing, b the WEDM process

Fig. 3 Representative roughness profiles of the 65 vol% SiCp/2024Al composite after the WEDM process

Fig. 4 Cross-sectional microstructure of 65 vol% SiCp/2024Al composite after the WEDM process: a SEM observation result, b corresponding schematic diagram

Fig. 5 Microstructure of the residual SiC particles on the surface after the WEDM process: a SEM observation, b magnification of red box area in a, c corresponding schematic diagram of b

Fig. 6 Representative morphology of the removed products of SiCp/2024Al composite after the WEDM process: a, b morphologies of different products, c-e corresponding EDS analysis of the red, blue box area in a and of the green box area in b, respectively

Fig. 7 Polished microstructure of the removed products of SiCp/2024Al composite after the WEDM process: a morphology, b, c corresponding EDS analysis of the red and blue box area in Fig. 2a, respectively

Fig. 8 Comparison of the XRD patterns of SiCp/2024Al composite and removed products after the WEDM process

Fig. 9 XPS analysis of the removed products of SiCp/2024Al composite after the WEDM process: a full spectrum, b narrow spectrum

Fig. 10 TEM and HRTEM observations of the removed products of SiCp/2024Al composite after the WEDM process: a irregular and b sphere products, c surface of irregular products, d corresponding SAED pattern of Si-O amorphous layer in c, e surface of sphere products, f corresponding SAED pattern of graphite layer in e