Fig. 1. Micro-morphologies of deposited powders. (a) Cu powder; (b) Cu-coated graphite powder

Fig. 2. Schematic diagram of SLD system

Fig. 3. Cross-sectional morphologies of composite coatings with different graphite contents and morphologies of joints between composite coatings and substrates when the laser irradiation power is 600 W. (a)(b) CuGr5; (c)(d) CuGr10; (e)(f) CuGr15

Fig. 4. XRD diffraction patterns for coatings with different graphite contents and Cu-coated graphite powder

Fig. 5. SEM images of cross sections of CuGr10 coating. (a) Middle of coating; (b) joint between coating and substrate

Fig. 6. Microstructures and element distributions of composite coatings with different graphite contents. (a) CuGr5; (b) CuGr10; (c) CuGr15

Fig. 7. Microhardnesses of substrate and composite coatings with different graphite contents

Fig. 8. (a) Friction coefficient curves and (b) mass losses of substrate and composite coatings with different graphite contents

Fig. 9. (a) Wear profiles and (b) wear rates of substrate and composite coatings with graphite contents

Fig. 10. Morphologies of worn surfaces of substrate and composite coatings with different graphite contents. (a1) Cu substrate; (b1) CuGr0; (c1) CuGr5; (d1) CuGr10; (e1) CuGr15; (a2)--(e2) enlarged images of areas in the dotted boxes in Figs. 10 (a1)--(e1)

Fig. 11. EDS analysis results of worn surfaces of composite coatings with different graphite contents. (a) CuGr0; (b) CuGr5; (c) CuGr10

Fig. 12. Raman spectra of abrasive surfaces of composite coatings with different graphite contents