The paper presents the results of experimental-numerical tests of firing at aluminum composite materials. The test materials were manufactured by pressure infiltration of porous ceramic preforms made of -Al2O3 particles in the amount of 30% and 40% by volume. The EN AW-7075 alloy was chosen as the material matrix, and the steel 7.62×39 mm (M 43) FMJ (Full Metal Jacket) intermediate ammunition was selected for firing. In the result of the experiment, the samples were perforated with a clear difference in the muzzle diameter. The projectile with fragments caused damage to up to three reference plates placed behind the samples (witness plates) in composites with 40% of particles by volume. The mechanics of crack propagation during ballistic impacts of the projectile was characterized based on microstructure studies. Then, using numerical analysis of impact load, the examination of composite materials puncture in the ABAQUS environment was carried out. The Finite Element Method (FEM) was employed for the discretization of geometric models using Hex elements. The Johnson-Cook constitutive model describing the relationship between stress and strain in metal-ceramic composites was applied for the analyses. Numerical models were then subjected to numerical verification using smoothed particle hydrodynamics (SPH). Based on the obtained results, it was found that the hybrid FEM/SPH method correlates significantly with the experimental results.

The paper presents results of bend tests at elevated temperatures of aluminium alloy EN AC-44200 (AlSi12) based composite materials

reinforced with aluminium oxide particles. The examined materials were manufactured by squeeze casting. Preforms made of Al2O3

particles, with volumetric fraction 10, 20, 30 and 40 vol.% of particles joined with sodium silicate bridges were used as reinforcement. The

preforms were characterised by open porosity ensuring proper infiltration with the EN AC-44200 (AlSi12) liquid alloy. The largest

bending strength was found for the materials containing 40 vol.% of reinforcing ceramic particles, tested at ambient temperature. At

increased test temperature, bending strength Rg of composites decreased in average by 30 to 50 MPa per 100°C of temperature increase.

Temperature increase did not significantly affect cracking of the materials. Cracks propagated mainly along the interfaces particle/matrix,

with no effect of the particles falling-out from fracture surfaces. Direction of cracking can be affected by a small number of

agglomerations of particles or of non-reacted binder. In the composites, the particles strongly restrict plastic deformation of the alloy,

which leads to creation of brittle fractures. At elevated temperatures, however mainly at 200 and 300°C, larger numbers of broken,

fragmented particles was observed in the vicinity of cracks. Fragmentation of particles occurred mainly at tensioned side of the bended

specimens, in the materials with smaller fraction of Al2O3 reinforcement, i.e. 10 and 20 vol.%.

The paper presents results of compressive strength investigations of EN AC-44200 based aluminum alloy composite materials reinforced

with aluminum oxide particles at ambient and at temperatures of 100, 200 and 250C. They were manufactured by squeeze casting of the

porous preforms made of α-Al2O3 particles with liquid aluminum alloy EN AC-44200. The composite materials were reinforced with

preforms characterized by the porosities of 90, 80, 70 and 60 vol. %, thus the alumina content in the composite materials was 10, 20, 30

and 40 vol.%. The results of the compressive strength of manufactured materials were presented and basing on the microscopic

observations the effect of the volume content of strengthening alumina particles on the cracking mechanisms during compression at

indicated temperatures were shown and discussed. The highest compressive strength of 470 MPa at ambient temperature showed

composite materials strengthened with 40 vol.% of α-Al2O3 particles.

The paper presents the results of research of impact strength of aluminum alloy EN AC-44200 based composite materials reinforced with

alumina particles. The research was carried out applying the materials produced by the pressure infiltration method of ceramic preforms

made of Al2O3 particles of 3-6m with the liquid EN AC-44200 Al alloy. The research was aimed at determining the composite resistance

to dynamic loads, taking into account the volume of reinforcing particles (from 10 to 40% by volume) at an ambient of 23°C and at

elevated temperatures to a maximum of 300°C. The results of this study were referred to the unreinforced matrix EN AC-44200 and to its

hardness and tensile strength. Based on microscopic studies, an analysis and description of crack mechanics of the tested materials were

performed. Structural analysis of a fracture surface, material structures under the crack surfaces of the matrix and cracking of the

reinforcing particles were performed.

The aim of this work is the development of Cu-Al2O3 composites of copper Cu-ETP matrix composite materials reinforced by 20 and 30

vol.% Al2O3 particles and study of some chosen physical properties. Squeeze casting technique of porous compacts with liquid copper

was applied at the pressure of 110 MPa. Introduction of alumina particles into copper matrix affected on the significant increase of

hardness and in the case of Cu-30 vol. % of alumina particles to 128 HBW. Electrical resistivity was strongly affected by the ceramic

alumina particles and addition of 20 vol. % of particles caused diminishing of electrical conductivity to 20 S/m (34.5% IACS). Thermal

conductivity tests were performed applying two methods and it was ascertained that this parameter strongly depends on the ceramic

particles content, diminishing it to 100 Wm-1K-1 for the composite material containing 30 vol.% of ceramic particles comparing to 400

Wm-1K-1 for the unreinforced copper. Microstructural analysis was carried out using SEM microscopy and indicates that Al2O3 particles

are homogeneously distributed in the copper matrix. EDS analysis shows remains of silicon on the surface of ceramic particles after

binding agent used during preparation of ceramic preforms.