The behaviour of aluminium matrix composites under thermal stresses

Abstract

The present review work elaborates the behaviour of aluminium matrix composites (AMCs) under various kinds of thermal stresses. AMCs find a number of applications such as automobile brake systems, cryostats, microprocessor lids, space structures, rocket turbine housing, and fan exit guide vanes in gas turbine engines. These applications require operation at varying temperature conditions ranging from high to cryogenic temperatures. The main objective of this paper was to understand the behaviour of AMCs during thermal cycling, under induced thermal stresses and thermal fatigue. It also focuses on the various thermal properties of AMCs such as thermal conductivity and coefficient of thermal expansion (CTE). CTE mismatch between the reinforcement phase and the aluminium matrix results in the generation of residual thermal stress by virtue of fabrication. These thermal stresses increase with increasing volume fraction of the reinforcement and decrease with increasing interparticle spacing. Thermal cycling enhances plasticity at the interface, resulting in deformation at stresses much lower than their yield stress. Low and stable CTE can be achieved by increasing the volume fraction of the reinforcement. The thermal fatigue resistance of AMC can be increased by increasing the reinforcement volume fraction and decreasing the particle size. The thermal conductivity of AMCs decreases with increase in reinforcement volume fraction and porosity.

Prediction of thermal and thermo‐mechanical behavior of nano‐zirconia reinforced aluminium matrix composites

“…Whereas, the results from representative volume model delivered thermal conductivity values as 131 W/m⋅K, 126 W/m⋅K, 107 W/m⋅K and 76.9 W/m⋅K for Al‐ZC0, Al‐ZC1, Al‐ZC2, and Al‐ZC3 respectively. The deviation of simulated results from experimental results is ∼1.9 % for Al‐ZC0, ∼5.03 % for Al‐ZC1, ∼3.35 % for Al‐ZC2, and ∼1.75 % for Al‐ZC3.This discrepancy in simulated and experimental values is attributed to the phenomena like percolation present in the experimental specimens owing to inclusions touching each other, are extremely complicated to model while inclusion are in lower volume fraction [13, 14]. The lower coefficient of thermal expansion of ceramic particles than aluminium alloys may be the cause of this behaviour.…”

“…The increasing zirconia content in the aluminium 6061 matrix causes thermal conductivity to decrease, [13,14]. The lower coefficient of thermal expansion of ceramic particles than aluminium alloys may be the cause of this behaviour.…”

Synthesis and characterisation of magnesium matrix composite reinforced with titanium dioxide nanoparticulates

“…In addition, this also reduces the thermal stress induced during heat treatment of sample. The authors [13,[17][18][19] reported that CTE mismatch is the reason for generation of thermal stresses during the composite fabrication, which can be minimised by controlled sintering temperature and the use of microwave sintering with SiC susceptors [20,21].…”

“…From this study, fine grain size, increase in tensile strength, increase in elongation and increase in hardness was observed in heat treated alloy. Khusbu Dash et al [13] studied the various thermal properties of aluminium matrix composite (AMC). The author concluded that thermal expansion mismatch and reinforcement volume in composite is the reason for generation of thermal stresses.…”

Discrete Element Framework for Determination of Sintering and Postsintering Residual Stresses of Particle Reinforced Composites

“…Modeling of stresses, defects, and, in consequence, damage of particle-reinforced composite materials induced by thermal loadings have been widely investigated, cf. [ 8 , 9 , 10 , 11 , 12 ]. Various approaches have been used in modeling of these phenomena.…”