Microstructure and shear strength of the C/SiC and Q235 brazing joints
-
摘要: 采用磁控溅射镀膜技术对碳/碳化硅复合材料(C/SiC)表面进行镀Ti金属化，以AgCu28为钎料，无氧铜为中间层与碳钢进行钎焊连接. 研究无氧铜中间层、Ti膜厚度和钎焊温度对接头组织形貌和力学性能的影响. 结果表明，采用无氧铜中间层可有效降低接头的残余应力，提高接头强度，并阻挡C/SiC复合材料中的Si元素在钎焊过程中扩散至碳钢侧，防止了碳钢界面FeSix恶性反应层的形成. 在试验范围内，钛膜厚度和钎焊温度与接头抗剪强度之间均存在峰值关系. 860 ℃，3 μm Ti膜接头平均抗剪强度最高，达到25.5 MPa. 由剪切试样碳钢侧断口，可观察到大量平行断口方向的碳纤维和碳纤维脱粘坑. 断裂发生在C/SiC复合材料内部距界面约300 μm处. C/SiC界面反应产物以Ti5Si3为主，含少量TiC. 钎缝中有TiCuSi相生成.Abstract: C/SiC composites were deposited with Ti coating by magnetron sputtering, and brazed to Q235 with copper interlayer using AgCu28 as filler. The effects of copper interlayer, thickness of Ti coating and brazing temperature on the microstructure and mechanical properties of joints were studied in details. The results show that Cu interlayer can effectively reduce the residual stress of the joint, and obstruct the diffusion of Si element to Q235 during brazing, thus preventing the formation of FeSix reaction layer. The thickness of Ti and the brazing temperature both show a peak relationship with the shear strength of the joint. The maximum shear strength achieved 25.5 MPa at 860 ℃ with 3 μm Ti coating. A lager number of C fibers and debonding pits can be observed on the fracture surface at Q235 side. The failure occurs within the C/SiC composite about 300 μm from the interface. The reaction layer at C/SiC interface are mainly composed of Ti5Si3 phases containing a small amount of TiC phases. TiCuSi phases are formed in brazing seam.
-
Keywords:
- C/SiC composite /
- Ti coating /
- interlayer /
- shear strength
-
-
![]()
图 2 840 ℃，15 min下铜中间层对接头的影响
Figure 2. Influence of interlayer on the joints brazed at 840 ℃ for 15 min. (a) SEM of the C/SiC-Q235 joint; (b) SEM of the C/SiC-Cu-Q235 joint
![]()
图 4 860 ℃，15 min下不同厚度Ti膜的C/SiC-Cu-Q235接头剪切断口 Q235 侧断口LSCM和SEM图像
Figure 4. Facture surfaces of the C/SiC-Cu-Q235 joints with different thickness Ti coating brazed at 860 ℃ for 15 min. (a) LSCM of the joint with 1 μm Ti; (b) LSCM of the joint with 3 μm Ti; (c) LSCM of the joint with 5 μm Ti; (d) SEM of the joint with 1 μm Ti; (e) SEM of the joint with 3 μm Ti; (f) SEM of the joint with 5 μm Ti
![]()
图 5 860 ℃下3 μm Ti膜C/SiC-Cu-Q235接头界面显微结构及元素分布
Figure 5. Interfacial microstructure and element distribution of C/SiC-Cu-Q235 joints with 3 μm Ti coating at 860 ℃. (a) SEM of the joint; (b) distribution of C; (c) distribution of Si; (d) distribution of Ti; (e) distribution of Cu; (f) distribution of Ag
-
[1] 王坤杰, 姚冬梅, 崔红, 等. 液体火箭发动机喷管延伸段C/C-SiC复合材料的性能[J]. 固体火箭技术, 2019, 42(4): 506 − 512. Wang Kunjie, Yao Dongmei, Cui Hong, et al. Performances of C/C-SiC composites for the nozzle extension of liquid rocket engines[J]. Journal of Solid Rocket Technology, 2019, 42(4): 506 − 512.
[2] Xiao Peng, Lu Yuhai, Lui Yizhong, et al. Microstructure and properties of Cu-Ti alloy infiltrated chopped Cf reinforced ceramics composites[J]. Ceramic International, 2017, 43(18): 16628 − 16637. doi: 10.1016/j.ceramint.2017.09.053
[3] Zhang Qing, Sun Liangbo, Liu Qingyong, et al. Effect of brazing parameters on microstructure and mechanical properties of Cf/SiC and Nb-1Zr joints brazed with Ti-Co-Nb filler alloy[J]. Journal of the European Ceramic Society, 2017, 37(3): 931 − 937. doi: 10.1016/j.jeurceramsoc.2016.09.031
[4] Wang Wanli, Fan Dongyu, Huang Jihua, et al. A new partial transient liquid-phase bonding process with powder-mixture interlayer for bonding Cf/SiC composite and Ti-6Al-4V alloy[J]. Materials Letters, 2015, 143: 237 − 240. doi: 10.1016/j.matlet.2014.12.110
[5] 沈元勋, 李正林, 郝传勇, 等. 银基钎料活性钎焊C/SiC-Ti55与Al2O3-Ti55接头界面组织[J]. 焊接学报, 2017, 38(9): 75−78. Shen Yuanxun, Li Zhenglin, Hao Chuanyong, et al. Microstructue of the C/SiC-Ti55 and Al203-Ti55 joints using Ag-based filler[J]. Transactions of the China Welding Institution, 2017, 38(9):75−78.
[6] Zhang Jie, Zhang Qiang, Liu Chunfeng, et al. Effect of brazing temperature on microstructure and mechanical properties of 2D Cf/SiC and Nb joints brazed with Co-Ti-Nb filler alloy[J]. Materials Science and Engineering A, 2015, 634: 116 − 122. doi: 10.1016/j.msea.2015.03.013
[7] Asthana R, Singh M. Joining of partially sintered alumina to alumina, titanium, Hastealloy and C-SiC composite using Ag-Cu brazes[J]. Journal of the European Ceramic Society, 2008, 28(3): 617 − 631. doi: 10.1016/j.jeurceramsoc.2007.06.017
[8] Lin G B, Huang J H. Brazed joints of Cf/SiC composite to Ti alloy using Ag-Cu-Ti-(Ti+C) mixed powder as interlayer[J]. Powder Metallurgy, 2006, 49(4): 345 − 348. doi: 10.1179/174329006X113454
[9] Yang Z W, He P, Zhang L X, et al. Microstructural evolution and mechanical properties of the joint of TiAl alloys and C/SiC composites vacuum brazed with Ag-Cu filler metal[J]. Materials Characterization, 2011, 62(9): 825 − 832. doi: 10.1016/j.matchar.2011.05.007
[10] Hernandez X, Jiménez C, Mergia K, et al. An innovative joint structure for brazing Cf/SiC composite to titanium alloy[J]. Journal of Materials Engineering and Performance, 2014, 23: 3069 − 3076. doi: 10.1007/s11665-014-1074-9
[11] 沈元勋. C/C和C/SiC复合材料与金属钎焊接头界面组织与性能研究[D]. 沈阳: 中国科学院金属研究所, 2012. Shen Yuanxun. Study on the interfacial microstructure and mechanical properties of the C/C composites-metal and C/SiC composites-metal joints prepared by brazing method[D]. Shenyang: Institute of Metal Research, Chinese Academy of Sciences, 2012.
[12] 王子晨, 曹建, 代翔宇, 等. Ag-Cu-WC复合钎料钎焊ZrO2陶瓷和TC4合金[J]. 焊接学报, 2019, 40(1): 5 − 9. Wang Zichen, Cao Jian, Dai Xiangyu, et al. Brazing ZrO2 ceramic and TC4 alloy using Ag-Cu+WC composite filler[J]. Transactions of the China Welding Institution, 2019, 40(1): 5 − 9.
[13] Yang Zhenwen, Lin Jiamei, Wang Ying, et al. Characterization of microstructure and mechanical properties of Al2O3/TiAl joints vacuum-brazed with Ag-Cu-Ti plus W composite filler[J]. Vacuum, 2017, 143: 294 − 302. doi: 10.1016/j.vacuum.2017.06.020
[14] Wang Zeyu, Wang Gang, Li Manni, et al. Three-dimensional graphene-reinforced Cu foam interlayer for brazing C/C composites and Nb[J]. Carbon, 2017, 118: 723 − 730. doi: 10.1016/j.carbon.2017.03.099
[15] Shen Yuanxun, Li Zhenglin, Hao Chuanyong, et al. Joining of C/C composite to copper using Cu-3.5Si braze[J]. Journal of Nuclear Materials, 2012, 421(1-3): 28 − 31. doi: 10.1016/j.jnucmat.2011.10.048
下载:
计量
- 文章访问数: 484
- HTML全文浏览量: 20
- PDF下载量: 28
