Many urgently needed inconel superalloy parts with complex internal cavity geometry and high surface precision are difficult to prepare by traditional subtractive manufacturing methods because of its poor machinability. The additive manufacturing technology that has emerged in recent years became a research hotspot in the manufacture of refractory and difficult-to-process metals. In the present study, selective laser melting (SLM), a typical additive manufacture technology, was used to prepare Inconel 718 samples. The influences of input laser energy density ((E, J/mm3) on densification behavior, phases composition, microstructures, microhardness, and wear performance of the SLM as-built Inconel 718 samples were explored in detail. X-ray diffraction (XRD), optical microscopy (OM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to examine the phase composition and microstructure evolutions. The results show that the formablity, microstructures and mechanical properties of the printed samples were all improved with the increase of E within the parameter setting range of this study. At a lower E, the poor surface morphology and balling effect occurred, the density, hardness, and wear resistance were all at a relatively lower level. When an E value of 190 J/mm was properly set, the surface open-pores and balling effect disappeared, the laser scanning tracks became smooth and continuous, the near-full dense (99.15%) and specimens with good metallurgical bonding and no critical defect were obtained, in which the average microhardness value reached 348 HV0.2 and wear rate was 5.67 × 10−4 mm3/N·m. The homogeneity of the superalloy Inconel 718 was also explored.

In this work, the synthesis of nanoscale CuInS and CuInSe was developed using molecular precursors of the type [(PhP)CuIn(ER)] (E = S, Se) and solvothermal reactions. Various conditions were investigated including the use of different precursors, reaction temperatures, reaction times and the addition of a secondary chalcogen source to mixtures. After optimizing conditions, nanoparticles of CuInS and CuInSe were isolated with controlled sizes in the range of 2-5 nm (wurtzite structure), which ultimately tuned the band gap energies of the materials. Characterization methods including powder X-ray diffraction, electron microscopy, and optical spectroscopy were used to investigate their structures and photophysical properties.

Wurtzite‐type monodisperse CuInS2 (I) and CuInSe2 (II) nanoparticles are prepared by controlled solvothermal reaction of (Ph3P)2CuIn(XEt)4 (X: S, Se; prepared according to the literature) and S8 (no additional Se source for CuInSe2) in THF (autoclave, 140—200 °C, 24 h).

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