Abstract
Damping behaviour of micro alloyed ductile and gray cast irons were investigated in this study. This was aimed at establishing the effect of composition and microstructural parameters on the damping properties of the micro alloyed cast irons, which have shown promise for utilization in automobile and machine building where enhanced damping performance are vital. Gray cast iron containing manganese as base metal was micro alloyed randomly with molybdenum, nickel, chromium and copper at an amount not more than 0.2 % each; magnesium was added to the melt prior to casting. The microstructures show that both ductile and gray irons were developed, ductile irons consisted of pearlite and ferrite phases with their nodular graphite surrounded by the ferrite phase. The micro-alloyed ductile irons generally had higher storage (78906.39 – 120868.51 MPa) and loss modulus (78906.39 - 120868.51MPa) than the micro-alloyed gray cast irons and the ductile iron composition without alloying elements. Although the damping capacity of the composition without micro alloying elements was highest for all the cast irons (~ 0.085), but it failed at approximately 110 ᵒC, while most of the micro-alloyed ductile irons exhibited satisfactory capacity for vibration energy dissipation up to 190 ᵒC than the micro-alloyed gray irons.
Highlights
The utilization of ductile irons has increased globally as a result of its good mechanical properties, low cost of production, and adaptability for mass production [1]
Rao et al [8] reported that manganese/copper ratio can be optimally selected for enhanced pearlite formation, which results in improved mechanical properties in ductile irons
The results indicated that: The Microstructures of the ductile irons contain pearlite, ferrite and graphite nodules with nodules count in various proportions
Summary
The utilization of ductile irons has increased globally as a result of its good mechanical properties, low cost of production, and adaptability for mass production [1] They possess moderate to low corrosion, fracture, wear resistance and damping capacity – properties that are critical requirements for several nascent automobile and machinery components [2, 3]. The damping capacity of cast irons is reported to be influenced by factors such as the internal friction mechanism of the graphite, graphite volume fraction, count and morphology, matrix structure, matrix phase surrounding the graphite, presence of alloying elements, among others [14,15,16] These microstructural variables are largely dependent on the composition, and processing deployed for the cast iron production [17, 18]. The impact on these phase and graphite parameters and the consequential effect on the damping properties of the specific alloy combinations selected as micro-alloying additions in this
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
