Variability in the mechanical properties and processing conditions of a High Strength Low Alloy steel

Variability in the mechanical properties of steel strip has a significant effect on the structural performance of manufactured components. This study provides a statistical analysis of the variability in yield strength, Ultimate Tensile Strength (UTS) and elongation to failure by examining the chemistry of the cast and rolling conditions of the steel strip. This type of data can play a key role in the development of robust and reliable new structures, as well as aiding process control specialists to minimise the variability during steel production. The steel grade under investigation is Hot Rolled (HR) S355MC; which is a High Strength Low Alloy (HSLA) steel and is widely used in the automotive sector for chassis & suspension applications. By using tree based classification models, the statistical distribution of mechanical properties could be determined and predicted by identifying key input criteria, such as the thickness of the steel strip, the niobium and carbon content and certain thermal processing conditions.