具有铼涂层的C/C复合材料与铌的真空钎焊
Research on vacuum brazing of C/C-Re composite to Nb
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摘要: 利用自制的Zr-Ni钎料对具有铼涂层的碳碳复合材料与铌进行真空钎焊,确定了接头典型界面组织为C/C-Re复合材料/(Re)/(Re,Zr,Nb)+NiZr/ NiZr2+NiZr/ NiZr+Nb/Nb. 结果表明,钎焊过程中,铼涂层厚度变小,向钎缝中扩散,并与钎料元素形成了固溶体组织(Re,Zr,Nb),当钎焊保温时间过长时,Re元素向钎缝大量溶解,铼涂层与C/C复合材料脱离. 随钎焊温度升高及保温时间延长,接头抗剪强度均呈现出先升高后降低的变化趋势. 确定最佳焊接工艺参数为钎焊温度为1 110 ℃,保温时间为20 min,此时钎焊接头室温抗剪强度为19 MPa.Abstract: The vacuum brazing of C/C-Re composite toNbwas successfully performed with the brazing fillers of Zr-Ni (atomic ratio 64:36) powder. The results show that the interface structures of joints with Zr-Ni fillers each has a total of four reaction layers. The microstructure of the C/C-Re/Zr-Ni/Nb joints is C/C-Re composite /Re/ (Re,Zr,Nb)+NiZr/NiZr2+NiZr/NiZr+Nb/Nb.Through dissolution process, the Re(Rhenium) coating became thinner and the (Re,Zr,Nb) solid solution increased. The joint mechanical properties are evaluated through joint shear strength test, and the conclusions are that the shear strength ofjoints rose up at first and then declined with the increase of brazing temperature and the extending of holding time.The optimum welding parameters are that the brazing temperature is 1 110 ℃ and the holding time is 20 min. Under the optimum welding parameters, the maximum environment temperature shear strength of joints with Zr-Ni fillers is 19 MPa.