ZrC薄膜对Nb与ZrB_2-SiC相互作用的影响

Effect of ZrC Thin Film on Preventing Reactions between Nb and ZrB_2-SiC

以ZrB2、SiC粉体为原料,通过等离子活化烧结在1800℃,30MPa,保温时间5min条件下制得出组织结构均匀致密度的ZrB2-SiC陶瓷块体;采用磁控溅射在Nb箔表面镀微米级别的ZrC薄膜。然后将Nb箔与ZrB2-SiC叠层进行烧结。利用XRD检测了产物物相,采用SEM和能谱分析观测了断口显微结构和元素分布。结果表明,当Nb箔表面无ZrC薄膜或薄膜被破坏后,产物中基本不存在单质Nb。当Nb箔表面保持有完整ZrC薄膜时,Nb金属相可以大量保留下来。当烧结温度低于1500℃时,ZrC薄膜可以有效阻止铌箔的与ZrB2、SiC的反应。镀有ZrC薄膜的Nb箔做中间层与ZrB2/SiC叠层材料的断裂韧性有明显提高,断裂韧性达到了9.66MPa·m1/2。

Using ZrB2, SiC powders as raw material, dense ZrB2-SIC ceramics were made through plasma activation sintering at 1800℃, 30 MPa, 5 min holding time. ZrC film on the Nb foil was made by magnetron sputtering. The ZrB2-SiC ceramic and Nb with ZrC film are sintered as a laminated material. The experimental investigating techniques consist in X-ray diffraction （XRD） and field emission scanning electron microscope （FE-SEM）. The results indicate that when the sintering temperature is under 1500 ℃, ZrC film can be well preserved and can prevent the reaction between ceramic and metal. The best fracture toughness is 9.66 MPa · m1/2