On the microstructure of ceramic hollow microspheres
Reads0
Chats0
TLDR
In this paper, the microstructure of the ceramic hollow microspheres as reinforcing element was investigated, and the results showed that the Al2O3 and SiO2 distribution was not equal; the Al 2O3 phase was embedded in the surrounding mullite and Si O2 phase in the form of needles.Abstract:
Metal matrix syntactic foams (MMSFs) are relatively new materials which have increasing interest in the field of aviation and packaging industry. They are metal matrix composites, and their porosity is ensured by the incorporation of ceramic hollow microspheres. In this paper the microstructure of the ceramic hollow microspheres as reinforcing element was investigated. SL150, SLG and SL300 type ceramic microspheres were investigated. They contain various oxides, mainly Al2O2 and SiO2. Energy dispersive X-ray spectroscopy (EDS) maps were recorded from the sections of the microspheres’ wall. The results showed that the Al2O3 and SiO2 distribution was not equal; the Al2O3 phase was embedded in the surrounding mullite and SiO2 phase in the form of needles. EDS along a line in aluminium matrix syntactic foams was carried out in order to investigate the possible reaction between the aluminium matrix and the ceramic microspheres. Due to the uneven distribution of Al2O3 rich particles, the molten aluminium can reduce the SiO2 rich parts of the microspheres and the wall of the microspheres become damaged and degraded. This chemical reaction between the microspheres and the walls can make the infiltration easier, but the resulting mechanical properties will be lower due to the damaged microsphere walls.read more
Citations
More filters
Journal ArticleDOI
Characteristic compressive properties of hybrid metal matrix syntactic foams
TL;DR: In this paper, an AlSi12 matrix hybrid MMSF with monomodal Globocer (Al 2 O 3 and SiO 2 based ceramic) and pure Fe reinforcements were produced by pressure infiltration.
Journal ArticleDOI
Metal matrix syntactic foams produced by pressure infiltration—The effect of infiltration parameters
TL;DR: In this article, metal matrix syntactic foams (MMSFs) were produced by pressure infiltration and two parameters of the infiltration process (pressure and time) were varied and the infiltrated length was measured as the function of infiltration parameters in order to get data for the implementation of pressure infiltration as mass-production of MMSFs similar to injection mould casting, especially in the short infiltration time range.
Journal ArticleDOI
Quasi-static and high strain rate response of aluminum matrix syntactic foams under compression
TL;DR: In this article, aluminum alloy matrix syntactic foams were produced by inert gas pressure infiltration and four different alloys and ceramic hollow spheres were applied as matrix and filler material, respectively, the effects of the chemical composition of the matrix and the different heat-treatments are reported at different strain rates and in compressive loadings.
Journal ArticleDOI
On the sintering mechanisms and microstructure of aluminium–ceramic cenospheres syntactic foams produced by powder metallurgy route
TL;DR: In this paper, the in situ reaction between silica (phase of mullite) and aluminium particles, apart from any degradation of the mullite cell wall and the precipitation of silicon in the matrix, changes the sintering mechanism of syntactic foams due to the formation of eutectic aluminium-silica liquid quantities.
Journal ArticleDOI
Effects of specimen aspect ratio on the compressive properties of Mg alloy foam
TL;DR: In this article, the effects of specimen aspect ratio (the thickness/width ratio, AR) on the compressive properties of closed-cell Mg alloy foams were investigated systematically and the results showed that the length of stress strain plateau stage extended and ideality energy absorption efficiency improved with the specimen AR increasing and the yield strength decreased.
References
More filters
Journal ArticleDOI
Compressive characteristics of A356/fly ash cenosphere composites synthesized by pressure infiltration technique
TL;DR: In this article, hollow fly ash particles (cenospheres) were pressure infiltrated with A356 alloy melt to fabricate metal-matrix syntactic foam, using applied pressure up to 275kPa.
Journal ArticleDOI
Plasticity and Damage in Aluminum Syntactic Foams Deformed under Dynamic and Quasi-Static Conditions
TL;DR: In this paper, synthetic foams were fabricated by liquid metal infiltration of commercially pure and 7075 aluminum into preforms of hollow ceramic microspheres, which exhibited peak strength during quasi-static compression ranging from −100 to −230 MPa, while dynamic compression loading showed a 10-30% increase in peak strength magnitude, with strain rate sensitivities similar to those of aluminum-matrix composite materials.
Journal ArticleDOI
Effect of reinforcement of flyash on sliding wear, slurry erosive wear and corrosive behavior of aluminium matrix composite
M. Ramachandra,K. Radhakrishna +1 more
TL;DR: In this paper, the wear and friction characteristics of the composite in the as-cast conditions were studied by conducting sliding wear test, slurry erosive wear test and fog corrosion test.
Journal ArticleDOI
Load partitioning in aluminum syntactic foams containing ceramic microspheres
Dorian K. Balch,David C. Dunand +1 more
TL;DR: In this paper, syntactic foams were fabricated by pressure-infiltrating liquid aluminum (commercial purity and 7075-Al) into a packed preform of silica-mullite hollow microspheres.
Journal ArticleDOI
Compression behaviors of cenosphere–pure aluminum syntactic foams
TL;DR: In this article, a new method was established to predict the compressive strength of cenosphere-aluminum syntactic foams, showing the relation between the relative wall thickness of the cenopshere and the Compressive Strength of such foams.
Related Papers (5)
Compressive properties of closed-cell aluminum foams with different contents of ceramic microspheres
Producing metal matrix syntactic foams by pressure infiltration
Load partitioning in aluminum syntactic foams containing ceramic microspheres
Dorian K. Balch,David C. Dunand +1 more