Aluminum Matrix Composite (AlSi7Mg2Sr0.03/SiCp) Pistons Obtained by Mechanical Mixing Method

Abstract

Metal matrix composites are undoubtedly a group of advanced engineering materials. Compared to unreinforced matrix material, they are characterized by increased strength, greater stiffness, increased wear resistance, better mechanical properties and dimensional stability at elevated temperatures as well as lower density. Due to its very favorable tribological properties for many years research has been conducted on the application of MMC in friction node. The article presents important technological aspects related to the production and properties of composite pistons. Under industrial conditions, a composite suspension (AlSi7Mg2Sr0.03/SiCp 10 vol %) was prepared to allow casting of the semi-finished pistons series. Machining parameters of the working surfaces of the piston were selected on the basis of the turning test made on PCD, PCNM and uncoated carbide tools. The tribological properties of the composite pistons were determined on the basis of the pin-on-disc and the abrasion wear. The scuffing tests carried out under real operating conditions have confirmed the possibility of using composite pistons in air compressors.

Scratch Testing of AlSi12/SiCp Composite Layer with High Share of Reinforcing Phase Formed in the Centrifugal Casting Process

“…The surface morphology of silicon carbide particles (SiC p -F240) and the particle size distribution histogram are presented in Figure 2. Such kind of reinforcement particle size distribution is advantageous due to the possibility of obtaining a homogeneous composite suspension by the stir casting method [33,34]. With the intention to improve the service properties of the product, especially its resistance to wear in friction conditions as well as thermal and dimensional stability, hard silicon carbide particles (SiCp) marketed by Saint Gobain as F240 grade with the average particle diameter of 50 µm were used as the component reinforcing the plastic aluminum matrix.…”

“…The surface morphology of silicon carbide particles (SiCp-F240) and the particle size distribution histogram are presented in Figure 2. Such kind of reinforcement particle size distribution is advantageous due to the possibility of obtaining a homogeneous composite suspension by the stir casting method [33,34].…”

“…The reinforcing component in the form of silicon carbide particles ( Figure 2) was introduced to modified aluminum alloy using the well-known stir casting method numbered, for many years now, among economically viable liquid-phase PMMCs fabrication methods [33][34][35][36]. The technological process was carried out on a PTA200/PrG station as per an original procedure developed by the present authors and described in detail in previously published papers [10,34,37]. The prepared composite suspension of 10 wt % of SiC p in AlSi12 was cast to graphite forms to obtain a half-product for the subsequent formation of a composite sleeve in the centrifugal casting process.…”

Liquid-Phase Sintering and Properties of PIMed 10-20 vol.% SiCp-Reinforced Aluminium Composites

“…Aluminium matrix composites have been increasingly recognized for engineering applications such as in the automotive, electronics, aerospace and biomedical fields for examples [1][2][3]. Their properties are dependent on selected materials utilized such as the matrix alloys and reinforcements.…”

“…where ρ Al , ρ SiC , and ρ binder are densities of aluminium alloy (2.78 g/cm 3 ) [10], SiC (3.20 g/cm 3 ) and multi-component binder (0.94 g/cm 3 ). Accordingly, V Al , V SiC and V binder are volume fractions of aluminium alloy, SiC p and multi-component binder respectively, where V Al + V SiC + V binder = 1 for equation (2) and V Al + V SiC = 1 for equation (3). Increasing SiC p content therefore deteriorates the sintered density, due possibly to agglomeration behaviour of high surface energy SiC p [11,12] during feedstock preparation.…”