Study on the mechanism of grain size and residual stress coupling distribution on the intergranular corrosion susceptibility of AZ31B magnesium alloy.

In this paper, homogenization heat treatment and laser shock peening (LSP) processes were successfully carried out regulate the microstructure (grain size, residual stress, and element distribution, ) of the AZ31B magnesium alloy substrate surface. Based on the regulated AZ31B magnesium alloy substrate surface, it further explored and analyzed the mechanism and influence pattern of the coupling distribution of grain size and residual stress on the intergranular corrosion susceptibility of the substrate surface. Scanning electron microscopy (SEM) was used to observe the surface morphology, scanning Kelvin probe force microscopy (SKPFM) to observe the surface potential, zero resistance ammeter (ZRA) and scanning vibrating electrode technique (SVET) to measure the galvanic current on the surface, and electrochemical tests were conducted to evaluate its surface corrosion behavior.

Research on the Mechanism of Femtosecond Laser Ablation Concave-Convex Microstructure Transformation.

The phenomenon of femtosecond laser ablation of convex structures from the bottom to the top is interesting. In this study, AZ31B magnesium alloy was used as the substrate to analyze the impact of the laser pulse energy and scanning speed on the morphology of concave-convex microstructures. Subsequently, a unified two-dimensional numerical model incorporating solid, liquid, and gas phases was established, and combined with experimental data, the mechanism and formation process of concave-convex transformation in magnesium alloy under laser ablation were revealed.

The influence of twinning on the corrosion behavior of AZ31B magnesium alloy.

This study investigates the effect of twinning on the corrosion behavior of AZ31B magnesium alloy using solid solution heat treatment (SHT) and laser shock peening (LSP) techniques. The corrosion characteristics are assessed by scanning electron microscopy (SEM), scanning Kelvin probe force microscopy (SKPFM), zero resistance ammeter (ZRA), scanning vibrating electrode technique (SVET), and electrochemical tests. Results indicate that the twinning region in AZ31B magnesium alloy, enriched with tensile twins induced by laser shock, demonstrates increased corrosion susceptibility.

Effect of thumbtack needle on functional constipation: A pragmatic randomized controlled trial.

Objective: Thumbtack Needling (TN) has been employed in the treatment of functional constipation (FC), although the existing evidence supporting its effectiveness is limited. This study is to evaluate the efficacy of TN in ameliorating FC.

Method: A total of 482 eligible patients were recruited and randomly assigned to the TN group or the Mosapride Citrate (MC) group.

Femtosecond Laser Preparation of Terracotta Warrior-like Pit Superhydrophobic Structure on Magnesium Alloy with Mechanical Durability and Corrosion Resistance.

Magnesium alloys are among the most promising materials for medical implants, and by preparing a superhydrophobic surface, the rate of corrosion can be effectively slowed down and durability be improved. However, the anticorrosion surfaces are inevitable to be damaged for the conventional micro-nanostructured superhydrophobic magnesium alloys, which highly limits their application prospects. This work proposes the development of a Terracotta Warrior pit superhydrophobic structure (TWPSS), consisting of a wall structure with a Terracotta Warrior-like pit and a lotus-like surface papillae structure within the wall.