Thermomechanical fatigue behavior of CGI 450 and CGI 500 cast irons

The vermicular cast iron grade 450 is widely used in engineering applications, primarily by the automotive industry fabrication of internal combustion engines. However, recent years, 500 has been developed, and new studies searching for replacement 450, with aim increasing high-performance engines life, as well reducing their weight, are development. Due to operational characteristics, these subjected simultaneously thermal mechanical cycles, which influence useful life. Therefore, characterization resistance types loads materials selection engines, very important. Thus, objective this work was study thermomechanical fatigue life two irons conditions close those subjected. were characterized chemical metallographic analyses tensile tests. tests carried out at temperatures ranging from 50 ºC 420 ºC, a dwell time 180 seconds. exhibited higher strength, ductility when compared strength. These properties related size distribution eutectic cells (graphite) matrix.