Reaction Process of Al8B4C7 Synthesized from Al2O3/B2O3/C Mixed Powder

Al8B4C2 was synthesized using aluminum oxide, boron trioxide and activated carbon as the starting materials. The effect of synthesis temperature on synthesis of Al8B4C2 was investigated. The results indicate that Al8B4C7 was synthesized using a mixture of aluminum oxide, boron trioxide and activated carbon by a carbothermal reduction process. With the heating temperature increasing, the Al2O3 content is decreased in the products while Al2OC content is increased firstly and then is decreased, up to the maximum at 1650 degrees C. Al8B4C2 is observed at 1650 C and the relative content of Al8B4C7 in the products is increased with the heating temperature increasing, up to the maximum at 1800 degrees C. Al8B4C2 grains synthesized at 1800 degrees C are plate-like with thickness of 25 mu m and size of about 100 mu m.