Analysis of Inclusion Core under the Weld Pool of High Strength and Low Alloy Steel

Abstract

Inclusion core in the weld pool of HSLA steel was directly observed by Time Resolved X-Ray Diffraction experiments. The aluminum concentration to oxide was changed from 0.48 to 1.52 through the experiments. The corundum alumina was identified in the weld pool and the population increased as the contents of aluminum increased. The results of TRXRD experiments was related to the direct observation of inclusion by TEM analysis and the formation process of inclusion in HSLA steel was summarized in the sense of overall microstructure evolution during welding. When an aluminum content was approaching stoichiometrical value to oxygen level, the corundum alumina reacted with glassy phase and spinel-type oxide was formed after solidification process of welding.