EVALUATION OF AUSTEMPERING STUDY OF FERRITIC CAST IRON

In this study, the effect of austempering temperatures on the structural characterization of ferritic spheroid cast irons was analyzed. Austempering was the austenitization of the materials in the temperature of 900 ºC for an adequate period to obtain a complete austenite structure and then quenching to an interval temperature. Subcritical diffusion times were achieved at 320, 420, and 520 ºC ausferrite temperatures for period of 1.5 h. Metallurgical description of samples was defined using optical microscopy, energy dispersive spectrometry, X-ray diffraction, microhardness. The austempering temperature had a remarkable effect on the phase variations of the ferritic ductile cast irons. The higher degree of austempering produced a coarser structure called ausferrite.