TiB2-Cu复合材料燃烧合成与二次致密化行为

采用燃烧合成技术制备了相对密度为90%左右的TiB₂-40Cu金属-陶瓷复合材料,为了进一步提高复合材料的力学性能,研究了TiB₂-40Cu金属-陶瓷高温压缩弹塑性变形行为,证明了高陶瓷体积分数下金属陶瓷在高温环境下具有一定的塑性行为。分别在1050℃、1090℃、1150℃对复合材料进行二次热压烧结,详细研究了工艺参数对TiB₂-40Cu复合材料二次热压变形、组织特征及力学性能的影响。结果表明:经过二次热压后,材料的相对密度和弯曲强度有了较大幅度的提高,在1090℃时,材料的相对密度达到了96%,弯曲强度达到605.5MPa。并从宏观和微观上分析了致密化机理,认为致密化过程是多种机制共同作用的结果。 

COMBUSTION SYNTHESIS AND TWO-TIME DENSIFICATION OF TiB2-Cu COMPOSITES

TiB2-40Cu ceramic-metal composite with the relative density of about 90% was prepared by combustion synthesis. The elastic-plastic deformation behavior of high temperature compression was studied in order to prove that TiB2-40Cu has certain plasticity in high temperature. On the basis of high temperature compression, the two-time hot pressing sintering was conducted at 1050℃,1090℃ and 1150℃ . The deformation behavior and the variation of microstructure and mechanical properties were investigated in detail. The results show that the relative density and the flexural strength increase greatly after two-time hot pressing. The relative density reaches 605.5 MPa and the flexural strength reaches 96% at 1090℃,and increases 12% and 6% respectively. Macroscopical and microcosmic densification mechanisms were studied. The results show that densification processes are affected by multiplicate mechanisms together.