ABSTRACT
The effect of Vanadium and Molybdenum addition on the mechanical properties of ductile cast iron has been investigated. Alloys of ductile cast iron samples of varying additions of Vanadium and Molybdenum from 0.1- 0.3% were produced into cylindrical test bars by sand casting process using "sandwiched" treatment method. Unalloyed ductile cast iron samples of the same base metal composition were also produced to serve as control and heat treatment samples. The heat treated samples were austenitized for the purpose of normalizing, hardening and tempering. Results of the mechanical properties revealed that tensile strength, yield strength and hardness increased from 456, 307N/mm2 and 290BHN respectively for the unalloyed samples to maximum values of 560, 407N/mm2 and 369BHN at 0.15% Vanadium addition and 562, 462N/mm2 and 362BHN at 0.15% Molybdenum additions. Beyond 0.15% addition of both Vanadium and Molybdenum led to decrease in values of some of the properties. The impact values for the Molybdenum alloyed ductile iron increased with Molybdenum addition, while that of Vanadium got to a maximum at 0.2%V before decreasing. The heat-treated samples have higher tensile and hardness values, they are however, inferior to the Vanadium and Molybdenum alloys in terms of impact values. The yield strength of alloy grades are in some cases higher than the heat treated grades.