Fig. 1.

Morphology, microstructure and reflectivity of aluminum matrix nanocomposite (AMNC) powders. a, b SEM images of AMNC powders with x = 0.25. c Magnified image of b, showing TiC nanoparticles coated on the surface of an Al micro particle. d, e SEM images of the cross sections of specimens with x = 0.25 and x = 1, respectively. The AMNC powders (x = 1) have a higher loading of embedded TiC nanoparticles than the AMNC powders (x = 0.25). f Reflectivity of aluminum powders without and with nanoparticles. The dashed vertical line indicates the laser wavelength at 1070 nm. g Comparison of the reflectivity at the wavelength of 1070 nm for aluminum powder specimens with and without nanoparticles. Scale bar, 40 µm in a, 1 µm in b, c, e, and 4 µm in d. The error bars in the measured reflectivity are the standard deviations (s.d.) calculated over three measurements