基板材料对激光熔化沉积制造Ti-48Al-2Cr-2Nb合金组织、织构、相和显微硬度的影响

本文研究了基体材料对激光熔化沉积Ti-48Al-2Cr-2Nb合金显微组织、织构、相组成和硬度的影响。随着沉积层数的增加,沉积层的显微组织由网篮状结构向等轴状结构转变,最终演变为层状结构。α2(Ti3Al)相逐渐减少,γ(TiAl)相逐渐增多。不同的TiAl合金层具有不同的显微硬度。随着沉积层数的增加,显微硬度降低。研究结果对于激光沉积制造TiAl合金制备具有可接受的组织、织构、相组成和显微硬度具有参考价值。     

Novel plating solution for electroless deposition of gold film onto glass surface

In this paper, a simple and environmentally friendly electroless plating solution of chloroauric acid (HAuCl₄) and hydrogen peroxide (H₂O₂) for depositing gold film onto (3-aminopropyl)-trimethoxysilane (APTMS) -coated glass surface has been developed. APTMS as an adhesive reagent was used to attach the gold nanoparticles (AuNPs) onto the glass substrate. These AuNPs could be regarded as the preferential nucleation or catalytic sites for gold electroless reduction, which accelerated the reduction of Au³⁺ on the glass surface and effectively prevented the formation of gold metal in the bulk solution. During the gold plating process, H₂O₂ as the reducing agent was thermodynamically capable of reducing Au³⁺ ions from the HAuCl₄ precursor to gold atoms, which deposited onto the glass surface and finally formed the continuous gold film. The resulting gold film was characterized with X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and atomic force microscope (AFM), respectively.