Investigation of production process parameters effects on the mechanical properties of Thermex rebar by Taguchi method

Thermex is a thermo-mechanical process which is used as an in-line operation after rolling process. By using this process, the yield strength of the rebar reaches to at least 500 MPa. Due to the importance of using high-strength rebars, in the present study, the influences of the process parameters on the rebar’s mechanical properties are investigated using experimental techniques. Considering four effective factors including water flow rate, Thermex pressure, rolling speed and different furnace temperatures, standard tensile tests were performed. The required experiments according to Taguchi method were designed and then the effect of mentioned parameters on the mechanical properties (yield strength, ultimate strength and ductility) of the rebar was studied. Statistical investigation includinf signal to noise (S/N) ratio and analysis of variance (ANOVA) showed that all the mentioned parameters have s significant influence on the mechanical properties. Based on the results, the optimal values of the parameters were determined to achieve optimal conditions of strength and ductility.