This study compares the microstructure and properties of pure Cu and Cu-5 wt.% Al2O3 composites fabricated by spark plasma sintering under strictly identical processing conditions at 800-1000°C. Pure Cu samples achieved near-full densification and exhibited a bimodal grain structure dominated by coarse grains with increasing sintering temperature. In contrast, the composite samples showed lower density and non-monotonic densification behavior, with a minimum relative density at 900°C and significantly refined equiaxed grains due to strong grain-boundary pinning by nano Al2O3 particles. The higher fractions of high-angle boundaries and pronounced orientation disruption were observed in the composite samples, while high-resolution analysis confirmed the presence of grain-boundary Al2O3-rich regions that restricted Cu grain coalescence and continuity of grain boundary migration. X-ray diffraction results confirmed the absence of reaction phases in both materials. Hardness peaked at 900°C for both samples, and the composite samples showed consistently lower hardness due to retained porosity. The apparent electrical conductivity of the composite displays a non-linear temperature dependence, reflecting the competing influences of densification, microstructural recovery, and the insulating nature of Al2O3.

Ti.Grade12 is widely used in chemical processing, power generation, and nuclear industries because of its excellent corrosion resistance and mechanical strength, enhanced by alloying elements such as Ni and Mo. Ceramic reinforcements such as TiN have been reported to significantly improve the surface hardness and wear resistance of titanium-based materials. Furthermore, nano-sized WC particles can suppress excessive intermetallic compound formation and stabilize the Ti matrix through grain boundary pinning and microstructural control mechanisms. However, strong interfacial bonding between Ti and ceramic reinforcements generally requires high temperatures and prolonged sintering times, which may induce undesirable secondary phase formation. Therefore, optimizing the mixing ratio of Ti, TiN, and WC is essential to achieve a homogeneous interface and a stable composite structure. In this study, a composite layered structure was fabricated on a Ti.Grade12 substrate using mixed Ti, TiN, and nano-sized WC powders via Spark Plasma Sintering. A composition of 60 wt% Ti, 35 wt% TiN, and 5 wt% WC formed a stable coating layer without secondary phases and achieved a micro vickers hardness of approximately 2400 Hv.

In today’s financial industry, Fintech (financial technology) has showed its role of an innovation-driving area, which can bring outstanding changes to the traditional financial market. This article will briefly introduce Fintech as well as its development in Vietnam. Besides, the research also provided a survey on experts’ opinions on the challenges to the promotion of Fintech application for the modernization of the banking-finance system in Vietnam. The survey results of 40 experts in banking with knowledge of Fintech identify five challenges faced by Fintech companies in Vietnam: (1) legal corridor; (2) infrastructure; (3) Fintech companies; (4) customers; and (5) human resources. From these five challenges/barriers, there are 14 detailed aspects. The results of the expert survey using descriptive statistics show that all five factors are assessed to be low and need to be better addressed in the future. The authors suggest several solutions for further development of Fintech to support the modernization of the banking-finance system in Vietnam: (1) quickly complete the regulatory framework; (2) introduce policies on tax exemption; (3) promote research and application of the benefits of block-chain technology; (4) utilize the abilities of the human resources; and (5) actively promote and popularize knowledge about Fintech.