Increasing the Strength/Toughness Combination of High Volume Fraction Particulate Metal Matrix Composites using an Al‐Ag Matrix Alloy

Abstract

Ceramic reinforced metals, despite superior properties such as specific stiffness, are often considered as too brittle for structural applications. We show that despite a high ceramic particle content (60 vol.%), aluminium matrix composites can be made to exhibit a fracture toughness matching that of unreinforced aluminium alloys, provided critical microstructural parameters are controlled. We here use an unconventional Al‐Ag matrix to simultaneously increase the strength and the toughness of this class of composite.

Ductile-to-brittle transition in tensile failure of particle-reinforced metals

“…Predicted strength values then reach those achieved along the fibres in Nextel alumina fibre-reinforced aluminium (Deve and McCullough, 1995), with much higher failure strains: such values obviously will not be achieved for real particulate alumina-reinforced aluminium composites, as matrix voiding and interface decohesion will by then also intervene. Still, if matrix properties can be optimized to resist internal damage by voiding or otherwise, the present analysis suggests that, if ceramic particles as strong as current engineering ceramic fibres are produced, isotropic metal-matrix composites with impressive performance characteristics should result; data to show this have been produced in pressure-infiltrated particle-reinforced aluminium composites (Miserez and Mortensen, 2004;Miserez et al, 2006Miserez et al, , 2004a. There is, hence, a good probability that transposing to particles, not only the analysis methods developed for fibres (as done here), but also performance characteristics of current engineering fibres, is a venue of untapped potential in the design of strong, stiff and tough lightweight composites.…”

Multi‐Criteria Material Selection of Monolithic and Multi‐Materials in Engineering Design

“…The sandwich panel in the traditional configuration of a refrigerated truck floor is not load-bearing since the key loadbearing components are the wooden stiffeners. [15] However, a load-bearing sandwich panel is obviously a possibility and one that might allow substantial weight saving.…”

“…[15] The truck floor is 2.5 m wide and 13.5 m long. The distance between chassis beams is 1.4 m. The normal applied load case is derived from a 24-ton payload uniformly distributed over a truck floor panel.…”

“…The width of a forklift wheel is 79 mm. Following Rasmussen and Staelens, [15] a safety factor of 2 has been applied to account for the dynamic effects of driving. All the design parameters are summarised in Table 2.…”

“…The traditional configuration of the floor panel of refrigerated trucks, reproduced from Rasmussen and Staelens. [15] Fig. 11.…”