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以 Si C陶瓷片为基体层 ,金属 W为夹层 ,热压烧结制成 Si C/W层状复合材料。 X射线衍射分析显示 :夹层中的 W与 Si C反应生成了 W5Si3和 WC,无金属 W存在。断面扫描电镜分析表明 :(1 )夹层由颗粒状晶体 (W5Si3)和片状晶体 (WC)组成 ,片状晶片重叠为二级层状结构。 (2 )基体层 (Si C层 )的断裂方式为裂纹沿晶断裂 :夹层的断裂方式有两种 :一是裂纹沿颗粒状晶体的晶界的沿晶断裂 ,二是裂纹穿过片状晶体的穿晶断裂 ,断口还观察到片状晶片的拨出。材料力学性能呈现的规律为 :夹层厚度在 1 0～ 50 μm内 ,随夹层厚度的增加 ,断裂韧性增加 ,抗弯强度下降
With Si C ceramic sheet as the base layer, the metal W as a sandwich, hot pressed into Si C / W layered composite material. X-ray diffraction analysis showed that W in the interlayer reacted with Si C to form W5Si3 and WC, and metal-free W was present. Cross-sectional scanning electron microscopy analysis shows that: (1) The sandwich consists of granular crystals (W5Si3) and lamellae (WC), and lamellar lamellae overlap into two lamellar structures. (2) The rupture mode of the base layer (Si C layer) is intergranular fracture: there are two modes of intercalation: one is intergranular fracture along the grain boundary of the granular crystal and the other is through the lamellar crystal Of the transgranular fracture, fracture also observed the allocation of chip wafers. The mechanical properties of the material presented as follows: the thickness of the interlayer is within 10 ~ 50 μm, the fracture toughness increases and the bending strength decreases with the increase of the interlayer thickness