The Research On Preparation And Properties Of Open-cell Aluminum Foam Reinforced With Ceramic

Aluminum foam is a kind of new material that in one of the advantages of structuralmaterial and functional material. It can be widely applied to aerospace, automobilemanufacturing, petrochemical industry, high-speed train, environmental protection andother fields, Because it has the light weight, high specific rigidity, coupled with its goodconductive thermal conductivity, electromagnetic shielding, sound absorption, noisereduction, high damping and recyclable, etc. So far, Seepage casting process is the mainmethod to be prepared for open-cell aluminum foam, and the industrial salt particles arethe main material to be prepared for precast block. But, the aluminum foam that is madeof salt particles is low porosity, whose hole is irregular, the connectivity of internal holeis weaker, and the period is longer.In this thesis, we take the spherical calcium chloride as precast block material, andtake industrial pure aluminum as matrix material, preparation of (nearly) spherical porealuminum foam using seepage casting method. Then, studying the performances ofrelated with open-cell Aluminum foam.First of all, the studies focus on the preparation process of open-cell aluminumfoam. Second, we study the influence of structure parameters which are open-cellaluminum foam (relative density and pore size) on its mechanical properties byquasi-static compression experiment. Then, the samples of open-cell aluminum foamwere treated by micro-arc oxidation, researched the influence of time on micro-arcoxidation ceramic membrane. Finally, Studying the impact of micro-arc oxidationceramic membrane on corrosion resistance and mechanical properties of aluminumfoam.Research results show that:1. The optimum process for open-cell aluminum foam: sintered perform: firstly,preheating20~60minutes under260℃~350℃, and then setting the temperature to580℃~650℃, sinteringseveral hours at the temperature, then close the furnace, cooling to room temperature in the furnace. Optimum parameters of die-casting:melting temperature is680℃~740℃, preheating mold and precast body to260℃~350℃, the pouring temperature is680~740℃.2. The stress strain curve of specimen only associated with the relative density ofaluminum foam, and it has no relationship to the pore size. Relative density ofaluminum foam is greater; its mechanical properties are better. In addition, Relativedensity of aluminum foam is greater; energy absorption capacity and energy absorptionefficiency are greater.3. With the increase of the micro-arc oxidation time, the number of holes isincreasing on ceramic membrane, pore size also corresponding changing, the color ofthe membrane is more and more deep, roughness and thickness of the membrane isbecoming bigger and bigger. With the increase of the relative density, the number ofholes is decreasing on the surface of membrane, and the size of the hole and distributionbecome non-uniform; the aperture of the perforated aluminum foam is smaller, and thenumber of holes on the surface of membrane is fewer, and the uniformity of hole sizeand distribution is worse.4. Ceramic membrane that treated by Micro-arc oxidation can improve corrosionresistance of the open-cell aluminum foam. The longer of the Micro-arc oxidation time,the corrosion rate of ceramic membrane became faster. Micro-arc oxidation treatmentcan improve the mechanical properties of open-cell foam aluminum, at the same time,the energy absorption properties and the energy absorption efficiency of the sampleswere improved; and the longer micro-arc oxidation time, the more its mechanicalproperties, energy absorption performance and energy absorption efficiency isimproved.