Chuansong Wu

Surface integrity and modification of electro-discharge machined alumina-based ceramic composite

Abstract Increasingly more applications require ceramic parts or components with good surface integrity. This paper attempts to study the surface integrity of electro-discharge machined engineering ceramics and their surface modification by ultrasonic polishing. Flexural strength is used for evaluating the effect of the two machining processes on the surfaces of the machined specimens. The distributions of the strength data are further analyzed by the Weibull statistical method to give quantitative measures of the surface integrity of the machined specimens.

Investigation on the bubble dynamic behaviors and corresponding regulation method in underwater flux-cored arc welding

Observed two bubble growth modes indicated that the stability of arc burning and bubble growth relied on each other. Under selected welding parameters, the maximum diameters of generated bubbles complied with approximately normal distribution. Higher preset welding parameters generated larger bubbles with gradually receding influences. Vaporization, condensation, and reactions happened rapidly inside the bubbles even after detachment and when coming to water surface. Gas-assisted underwater flux-cored arc welding was proposed to improve the slag coverage. This method was also effective in achieving better weld appearance.