The influence of final coiling temperature on the microstructure and mechanical properties of high Ti-V HSLA steels

Abstract

In general, the strength-to-weight ratio is a marked property of high- strength low-alloy steel. The coiling temperature is an important process parameter in the control and improvement of final microstructure and mechanical properties. In this work, the effect of deformation and coiling temperature on microstructure and mechanical properties of high Ti- V microalloyed HSLA steels were investigated using the Gleeble 1500TM thermomechanical processing simulator. The samples were austenitised at 1150 ˚C for 300 s, then deformed in 4 passes at 1050, 1000, 950 and 900 ˚C. After final pass, the samples were cooled and isothermally held for 1800 s to simulate the coiling process at 550 and 650 ˚C. The results showed that at low coiling temperature (LCT) of 550 ˚C, the microstructures consisted of ferrite and bainite and also had higher hardness (304 HV).