The Influence of the Grain Size of the Matrix Material on the Mechanical Properties of MMC Made Through Powder Metallurgy Route
Mutlu Karasoglu Serdar Karaoğlu
AbstractAbstract Magnesium (Mg) has a density of 1,74 g/cm3, which is known as the lightest structural metal [1]. This significant characteristic makes Mg a good candidate for potential applications in automotive and aerospace industries to reduce fuel consumption [2]. However, poor mechanical properties of Mg such as low elastic module, limited high strength, low ductility and creep resistance at elevated temperature, restrict application of Mg [3]. Many efforts have been made by researchers in order to improve these weak features of Mg for decades. Some of the researchers have focused on grain refinement of Mg alloys [4-6], texture [7] and magnesium matrix composites (MMC) [8-10]. Magnesium matrix composites have many benefits such as high strength and elastic module, excellent wear and creep resistance compared to monolithic Mg. Enhancement in strength due to the addition of particle reinforcement, usually decreases ductility of material in conventional composites which limits application potential of MMC [11]. Although many researcher achieved increase in both strength and ductility by using nano-scaled reinforcements [12, 13], there is no attempt to reduce the grain size of the matrix. It is well known that nanocrystalline materials have lower diffusion activation energy and much higher diffusion coefficient, it can be considered to have a potential to yield a high density and good interface bonding with reinforcement in MMC’s. Nanocrystalline metals have higher ductility than coarse grained metals, hence nanocrystalline matrix can be used to compensate the low ductility of MMC’s. In this work, two different grain sized matrix materials were utilized to investigate the effect of the grain size of the matrix on mechanical properties on MMC.