Vol. 3, Issue 12, Part E (2017)

Connecting rods operate under high loads needs high strength in both tension and compression and high fatigue strength. For fulfilling that need here we have selected typical forged steel or ultra-high strength steel. This steel has strength level above 900MPa and this steel generally have carbon content ranging from 0.01-0.45%. It is well known that, as strength increases, toughness reduces. So toughness of ultra-high strength steel is an important consideration. As strength increases, critical length/size of defect decreases. Once the critical length of the defect is reached during processing or application, the material fails catastrophically without any prior warning. Ultra high strength steels are classified according to their composition microstructure. The steel C-70 has been introduced from Europe as crack able forging steel. Alloying elements in the material enables hardening of forged connecting rods when they undergo controlled cooling after forging. Hence a comparative study of these two materials for fatigue loading is the main goal of this paper. The model was developed in Pro/E wildfire 5.0 and then imported as parasolid (IGES) form in ANSYS workbench.