Materials

Half-cell potential (HCP) measurement is widely applied as a non-destructive technique for assessing corrosion probability, yet its diagnostic capacity remains limited to probabilistic interpretations rather than quantifying the extent of steel mass loss. Conventional HCP measurements can indicate corrosion probability, but not the actual extent of deterioration. The objective of this study is to examine the potential of HCP measurements to indicate actual corrosion severity by numerically simulating HCP values and correlating them with steel mass loss data. Using published experimental datasets, relationships among corrosion current density (J₍corr₎), electrical resistivity (ER), HCP, and steel mass loss (m_L) were established through regression analysis, while COMSOL Multiphysics v6.2 was employed to simulate HCP responses. The simulations revealed increasingly negative HCP values with higher J₍corr₎ and conductivity. A second-order polynomial correlation (R² = 0.9999) was obtained between simulated HCP and measured mass loss (0–20%), enabling quantitative interpretation of corrosion severity, demonstrating that HCP can serve as a predictive indicator of corrosion severity. It is demonstrated that the interpretative value of HCP has potential for quantifying corrosion severity to improve monitoring and maintenance strategies.

Metals with a hexagonal close-packed (HCP) structure such as magnesium, titanium and zirconium constitute key structural materials in the aerospace, automotive, biomedical and nuclear energy industries. Their welding and regeneration by conventional methods is hindered due to the limited number of slip systems, high reactivity and susceptibility to the formation of defects. Laser technologies offer precise energy control, minimization of the heat-affected zone and the possibility of producing joints and coatings of high quality. This article constitutes a comprehensive review of the state of knowledge concerning laser welding, cladding and regeneration of HCP metals. The physical mechanisms of laser beam interactions are discussed including the dynamics of the keyhole channel, Marangoni flows and the formation of gas defects. The characteristics of the microstructure of joints are presented including the formation of α′ martensite in titanium, phase segregation in magnesium and hydride formation in zirconium. Particular attention is devoted to residual stresses, techniques of cladding protective coatings for nuclear energy with Accident Tolerant Fuel (ATF) and advanced numerical modeling using artificial intelligence. The perspectives for the development of technology are indicated including the concept of the digital twin and intelligent real-time process control systems.

This work investigates the laser-based solid-phase crystallization of wet-chemically deposited BZY (yttrium doped barium zirconate) thin films on metallic substrates. For this purpose, amorphous BZY thin films are deposited on nickel-based alloy substrates using spin coating and are then annealed using laser radiation. Different laser intensities and scanning velocities are investigated. X-ray diffraction analysis of the processed thin films shows an initial increase in crystallinity with increasing laser intensity. A further increase in laser intensity leads to the formation of secondary phases and ultimately to the melting of the substrate material. Complete crystallization of the thin films without the formation of secondary phases is achieved by applying scanning velocities of $v_S$ ≥ 500 mm/s. Scanning electron microscopy images of selected samples show that, especially at higher scanning velocities, crack formation can occur as a result of the annealing. In summary, laser annealing is a promising approach for the thermal post-treatment of BZY thin films in applications in metal-supported solid oxide fuel cells.