Fig. 1. SEM morphology of 70W-30Cu composite powder

Fig. 2. Relative density of alloys with different W contents

Fig. 3. EDX map-scanning results of different alloys. (a) 70W-30Cu; (b) 80W-5Ni-15Cu

Fig. 4. SEM microstructures of different alloys. (a)(b) 60W-40Cu; (c)(d) 70W-30Cu; (e)(f) 75W-25Cu; (g)(h) 80W-5Ni-15Cu

Fig. 5. (a) Surface tension and (b) Marangoni flow controlled by temperature gradient in melt pool

Fig. 6. Thermal conductivity ofalloys with different W contents

Fig. 7. Coefficients of thermal expansion of alloys with different W contents

Fig. 8. Microstructures of bonding interface in test of coefficient of thermal expansion for different alloys. (a) 75W-25Cu; (b) 80W-5Ni-15Cu

Fig. 9. Surface roughnesses of composites with different W contents

Fig. 10. SEM surface morphologies of composites. (a) 60W-40Cu; (b) 70W-30Cu; (c) 75W-25Cu; (d) 80W-5Ni-15Cu

Fig. 11. Hardnesses of composites with different W contents