Effect of cooling rate and magnesium content on machinability and wear characteristics of ductile iron

Four grades of ductile iron containing magnesiumcontent from 0.02 % to 0.08 % were casted using a steppedpattern, which gives ductile irons of different coolingrates, in green sand with pressurized gating system.The Fe - si - Hg 5 % as a nodulizing alloy ( 5-8 mm)diameter was used using the inmold production technique.The tool life of the casted alloys was investigated in bothmilling and drilling processes. Also, the effect of castingcooling rates, magnesium content and heat treatments on wearresistance of ductile iron was investigated.The wear tests were carried out using a strip - shafttest - rig for a constant interval of time of 30 min.under constant sliding speed of 4.4 m / sec.The results showed a longer tool life for the ductileiron containing 0.04 % Mg and for the thinnest sectioncastings. The effect of cutting speed was less pronouncedthan the effect of both Mg % and cooling rate on the tool