Pressureless Infiltration Method B < Sub > 4 < / Sub > C - Ceb < Sub > 6 < / Sub > / 2519 A Composite Material Research Of Organizational Performance

In the article, making CeO2as additive, by in-situ reaction of CeO2and B4C, CeB6is introduced to increase the toughness of B4C preform. Then pressureless infiltration method is used to prepare B4C-CeB6/2519A composites. And at last heat-treatment process on the B4C-CeB6/Al composites is explored. The phase, microstructure, fracture surface of the composites are determined by XRD, SEM,EDS and so on. And the mechanical properties are tested by three point bending, single edge notched beam and so on.In this paper, the main conclusions are as follows:(1)the optimum process of preparing B4C-CeB6/Al composites by pressureless infiltration method is as follows:adding3wt%CeO2, molding pressure adopting100MPa and sintered at1800℃/2h, B4C-CeB6porous ceramic is prepared.(2) In the condition of the test in the article, CeO2and B4C react completely, and generate CeB6, dispersion of distribution. The preform has rounded particles. And sintered neck appears between the particles. It has a good intensity.(3)Adding3wt%CeO2, B4C-CeB6/Al composites’properties is as follows:Density is2.59g·cm-3; Hardness(HRA) is66.1; Bending strength is410.4MPa; Fracture toughness is6.95MPa· ml/2.(4)Through heat-treatment of660℃, B4C-CeB6/Al composites(3wt%CeO2) mainly inclue such phases as Al, B4C, A13BC, A1B2, CeB6, and CuAl2.(5)Through heat-treatment of900℃, B4C-CeB6/Al composites(3wt%CeO2) mainly inclue such phases as Al, B4C, A13BC, CeB6, and CUAl2. And Al phase has a huge decrease in amount. In the composites Al3BC increase obviously along with time extended.(6)The hardness of the composites through heat-treatment in900℃is higher than in660℃. The optimum heat-treatment process is900℃/25h.