The goal of this study is to empirically investigate the major hot rolling processparameters affecting the yield strength, ultimate tensile strength and strain-hardeningexponent of Nb-microalloyed steel sheets. The parameters considered were the roughing,finishing and coiling temperatures. Three levels for each parameter were used to develop amodel relating the process parameters to mechanical properties. By applying the responsesurface methodology, analysis of variance was done to determine the mathematical modelsrelated to each response. The results indicated that decreasing the coiling and finishingtemperatures significantly influenced the mechanical properties. Also, the modelspredicted that the maximum yield strength, ultimate tensile strength and strain-hardeningexponent are simultaneously obtained under the following conditions: roughing temperature= 1097 °C, finishing temperature = 837 °C and coiling temperature = 580 °C. The predictedvalues were close to the experimental values, indicating the suitability of themodels.
