Preparation And Optimization Of Magnesium Foam On LED Lamp Cooling Applications Research

With the development of science and technology, metal foams, amulti-function structural material, have got widely attention at home and abroad.The scientists involved have done a lot of research and got great progress. Butmore efforts still needs to be done on the control of preparation methods and theperformance research in order to ensure the metal foam widely used more andmore.This paper mainly focus on the vacuum infiltration process and the heatdissipation performance of magnesium foams. Through orthogonal experimentsthe influence of various process parameters on the infiltration process wasstudied, and the optimum parameters under the laboratory condition weredetermined. The foam magnesium radiators with different structure parameterswere made to study the heat dissipation performance under the condition ofnatural convection of foam magnesium. And through comparing with thecooling effect of the original radiator of LED lamp, the heat dissipationmechanism was analyzed.The results are as follows:(1) To optimize the preparing technology of foam magnesium: theinfluence of the preheating temperature of salt particles, the vacuum degree andthe pouring temperature of molten magnesium on the filling length of the samplewas studied. The results showed that the preheating temperature had the greatesteffect, vacuum degree second and the pouring temperature the least. Theoptimum infiltration parameters were determined as: the preheating temperatureof salt particles550℃, the pouring temperature720℃, the vacuum degree0.04MPa.(2) The infiltration mechanism was studied according to the heat transfertheory. The results showed that the effective length of the samples increasedwith the increasing of the superheat degree and the preheating temperature ofsalt particles. To prepare the larger size foam magnesium samples, it was feasible to increase the preheating temperature and the pouring temperature ofliquid properly.(3) Based on the radiator of the LED lamp, the heat dissipationperformance of foamed magnesium with different structural parameters. Theanalysis results showed that many factors could influence the heat dissipationproperties of foamed magnesium, the pore size had the most effect, the porositysecond, the base thickness the least. The optimun structural parameters of thefoamed magnesium is determined as：the pore size1.1~2.2mm, porosity60%and the base thickness0mm under the laboratory conditions. Compared withthe original radiator, the radiator with the above structure can reduce LEDtemperature1.2~3.9℃.