以高温钛合金和自共晶镍硅合金为母材，使用额外添加硼元素的Ti-Zr-Ni-Cu非晶钎料进行钎焊连接，针对硼元素含量和钎焊对接头界面结构和力学性能的影响进行探究。通过对Ni-25at% Si/Ti-Zr-Ni-Cu+B非晶钎料/Ti600接头的界面组织结构进行优化实现钎焊结构性能的提升，获得质量良好的钎焊接头。研究结果表明，通过引入硼元素可调控钎焊过程，继而获得TiB晶须，这种晶须能对Ti2Ni层产生复合强化的作用，进而使接头高温钛合金侧界面的残余应力明显下降，减缓接头开裂的速度，同时结合拔出强化方式对裂纹的扩展起到阻碍作用，从而提高接头的强度。1 213 K/10 min工艺条件下的镍硅合金/高温钛合金钎焊接头的平均强度高于不含硼元素增强的接头，达到84 MPa，同时确保在接头内部不会出现裂纹和孔洞，进而达到提升镍硅合金/高温钛合金钎焊接头质量的效果。
The Ti-Zr-Ni-Cu amorphous brazing filler metal with added boron element was used to braze high temperature titanium alloy and self eutectic silicon nickel alloy, and the effects of boron element content and brazing process on the interface structure and mechanical properties of the joint were explored. The interface structure of Ni-25at%Si/Ti-Zr-Ni-Cu+B amorphous brazing filler metal/Ti600 brazing joints was optimized to obtain higher performance joints. The research results show that by introducing boron element to metallurgically control the brazing process, TiB whiskers were obtained, which can produce compound strengthening effect on the Ti2Ni layer, significantly reduce the residual stress at the Ti600 side interface of the joint, delay crack, hinder crack propagation of the joint by pull-out strengthening, and thus improve the strength of the joint. The average strength of the Ni-25at%Si/Ti600 brazing joint under the 1 213 K/10 min process conditions was increased to 84 MPa, and there were no cracks and holes inside the joint. Quality of the Si-Ni alloy/high temperature titanium alloy brazing joint was successfully improved.
[1] ZHU J H, LIU C T. Intermediate-temperature mechanical properties of Ni-Si alloys:Oxygen embrittlement and its remedies[J].Intermetallics, 2002, 10(4):309-316.
[2] LIU L, MA X L, ZHAO S. Microstructure and hardness of Ni-xSi alloys[J].Journal of Shanghai Jiaotong University (Science), 2012, 17(6):648-652.
[3] LU Y P, LIU N, SHI T, et al. Microstructure and hardness of undercooled Ni78.6Si21.4 eutectic alloy[J].Journal of Alloys and Compounds, 2010, 490(1-2):L1-L4.
[4] FAN K, LIU F, YANG G C, et al. Precipitation in as-solidified undercooled Ni-Si hypoeutectic alloy:Effect of non-equilibrium solidification[J].Materials Science and Engineering:A, 2011, 528(22-23):6844-6854.
[5] KARAKÖSE E, KESKIN M. Microstructure evolution and mechanical properties of intermetallic Ni-xSi (x=5, 10, 15, 20) alloys[J].Journal of Alloys and Compounds, 2012, 528:63-69.
[6] 郑玉峰. Ni基金属间化合物合金的成分设计与激光制备[D]. 兰州:兰州理工大学, 2008:1-4. ZHENG Y F. Composition design and laser fabrication of nickel-based intermetallic compound alloys[D]. Lanzhou:Lanzhou University of Technology, 2008:1-4(in Chinese).
[7] DING X F, LIN J P, ZHANG L Q, et al. Lamellar orientation control in a Ti-46Al-5Nb alloy by directional solidification[J].Scripta Materialia, 2011, 65(1):61-64.
[8] 张辉. 新型金属焊接技术及其应用[J].科技研究, 2014(25):145. ZHANG H. New metal welding technology and its application[J].Science and Technology Research, 2014(25):145(in Chinese).
[9] 黄万群, 李亚江, 王娟, 等. 陶瓷/金属钎焊与扩散连接的研究现状[J].焊接, 2007(4):11-13, 62. HUANG W Q, LI Y J, WANG J, et al. Research status of brazing and diffusion bonding of ceramic and metal[J].Welding & Joining, 2007(4):11-13, 62(in Chinese).
[10] QI X S, XUE X Y, TANG B, et al. Microstructure evolution at the diffusion bonding interface of high Nb containing TiAl alloy[J].Materials Science Forum, 2015, 817:599-603.
[11] CHAI L, HUANG J H, HOU J B, et al. Effect of holding time on microstructure and properties of transient liquid-phase-bonded joints of a single crystal alloy[J].Journal of Materials Engineering and Performance, 2015, 24(6):2287-2293.
[12] LI X P, WANG H Q, WANG T, et al. Microstructural evolution mechanisms of Ti600 and Ni-25% Si joint brazed with Ti-Zr-Ni-Cu amorphous filler foil[J].Journal of Materials Processing Technology, 2017, 240:414-419.
[13] 杨卫岐. ZrB2-SiC陶瓷连接接头中原位TiB晶须生长机制及增强机理研究[D]. 哈尔滨:哈尔滨工业大学, 2014:108-110. YANG W Q. Research on the growth and reinforcing mechanisms of in situ TiB whiskers in ZrB2-SiC ceramic joints[D]. Harbin:Harbin Institute of Technology, 2014:108-110(in Chinese).
[14] 王颖. Al2O3陶瓷的反应金属化及其与5A05合金扩散钎焊机理研究[D]. 哈尔滨:哈尔滨工业大学, 2010:70-82. WANG Y. Research on mechanism of alumina ceramic reactive metallization and its diffusion brazing with 5A05 alloy[D]. Harbin:Harbin Institute of Technology, 2010:70-82(in Chinese).
[15] SATO H, KIKUCHI R. Correlation factor and Nernst-Einstein relation in solid electrolytes[M]//Mass Transport Phenomena in Ceramics. Boston:Springer US, 1975:149-154.
[16] MEYER A, PETRY W, KOZA M, et al. Fast diffusion in ZrTiCuNiBe melts[J].Applied Physics Letters, 2003, 83(19):3894-3896.
[17] CHEN Z W, WANG X, GIULIANI F, et al. Microstructural characteristics and elastic modulus of porous solids[J].Acta Materialia, 2015, 89:268-277.
[18] CLYNE T W, WITHERS P J. An introduction to metal matrix composites[M]. Cambridge:Cambridge University Press, 1995:100-104.
[19] 柏振海, 黎文献, 罗兵辉, 等. 一种复合材料弹性模量的计算方法[J].中南大学学报(自然科学版), 2006, 37(3):438-443. BAI Z H, LI W X, LUO B H, et al. A calculation method of elastic modulus of composites[J].Journal of Central South University (Science and Technology), 2006, 37(3):438-443(in Chinese).
[20] 柯阳林. 纳米SiC晶须改性Ti(C,N)基金属陶瓷的组织与性能研究[D]. 武汉:华中科技大学, 2007:55-56. KE Y L. Research on microstructure and properties of nano-SiC whisker modified Ti(C,N)-based cermets[D]. Wuhan:Huazhong University of Science and Technology, 2007:55-56(in Chinese).
[21] 关明星, 王铎, 王德尊. 晶须增强铝合金中短裂纹的疲劳扩展速率[J].哈尔滨工业大学学报, 1999, 31(5):60-62. GUAN M X, WANG D, WANG D Z. Fatigue propagation rate for short crack in whisker reinforced aluminium alloy[J].Journal of Harbin Institute of Technology, 1999, 31(5):60-62(in Chinese).
CJA