Improving high strength HSLA steel using a new model
High strength low alloy steels (HSLA) are low carbon steels that contain small additions (0.001–0.1 wt%) of alloying elements such as Nb, Ti, or V. These steels exhibit an outstanding combination of high strength, resistance to brittle fracture and good weldability.
The nature of precipitation and the solution temperature of the precipitates are crucial factors in controlling the strength of these steels. A generalized model to describe the precipitation behavior assists in intelligent alloy design and in establishing the optimum processing parameters.
• Characterisation of the dissolution of precipitates in the slab material of HSLA steel.
• Performing dissolution annealing and characterization conform hot mill processes.
• Model development to predict the dissolution of precipitates.
• A method was developed to characterise different precipitates (such as TiNb(CN), AlN and MnS).
• A model was tuned (Dictra, MatCalc) aimed at industrial benefits.
• The necessary furnace temperature was determined for each micro-alloyed HSLA steel.
• Cost reduction by lowering furnace temperature (from 1240 to 1150°C) resulted in savings of € 0.5 million/year!