Effect of quench and strain aging on the mechanical properties of low carbon microalloyed steels

Abstract

In this study, the aging behaviors of high strength low alloyed (HSLA) HC380LA quality steel were investigated. Steel samples were heated in a heat treatment furnace up to 950 degrees C and kept there for 1 hour, and then quenched in water. Some of the water quenched samples were aged at temperatures between 50-350 degrees C for 20 min (quench-aged, QA), while the other samples were exposed to the same aging procedure after a 3 % prestraining (strain-aged, SA). Experimental results showed that aging occurred in all QA and SA samples. The highest values for both QA and SA samples were obtained at aging treatment performed at 150 degrees C for 20 min. When the aging temperature increased to 200, 250, 300 or 350 degrees C, aging strength decreased. Results of the study suggest that different aging temperatures have an effect on the microstructure and on the mechanical properties of high strength low alloyed steels.