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采用Cu_(39.37)Ti_(32.19)Zr_(19.38)Ni_(9.06)(原子比)非晶态钎料对ZrB_2-SiC超高温陶瓷进行钎焊。通过X射线衍射、扫描电镜、万能试验机对钎料的微观结构以及钎焊接头形貌、析出相和室温力学性能进行系统分析。结果表明:在一定钎焊温度下,随钎焊时间的增加,接头剪切强度逐渐减小,且伴随裂纹的出现。在钎焊温度1183 K,钎焊时间30 min时获得的剪切强度最高,约为160 MPa。润湿性实验表明该非晶钎料在ZrB_2-SiC陶瓷表面的润湿性良好。接头剪切强度与钎料和母材之间的反应层厚度有关,通过计算得出反应层厚度形成的激活能Q和反应层生长速度A_0,建立了反应层生长规律的表达式。
The brazing of ZrB_2-SiC ultra-high temperature ceramic with Cu_ (39.37) Ti_ (32.19) Zr_ (19.38) Ni_ (9.06) (atomic ratio) The microstructure of the solder, the morphology of the solder joint, the precipitated phase and the mechanical properties at room temperature were systematically analyzed by X-ray diffraction, scanning electron microscopy and universal testing machine. The results show that under certain brazing temperature, the shear strength of the joint decreases gradually with the increase of brazing time, accompanied by the appearance of cracks. The highest shear strength is obtained at a brazing temperature of 1183 K and a brazing time of 30 min, which is about 160 MPa. Wettability experiments show that the amorphous solder on the ZrB_2-SiC ceramic surface wettability is good. The shear strength of the joint is related to the thickness of the reaction layer between the filler metal and the base metal. By calculating the activation energy Q and the growth rate A_0 of the reaction layer, the expression of the growth law of the reaction layer is established.