界面微觀組織的影響
(1. 哈爾濱工業(yè)大學(xué) 現(xiàn)代焊接技術(shù)國家重點(diǎn)實驗室， 哈爾濱 150001;
2. 北京礦冶研究總院, 北京 100001)
摘 要: 研究了Ti3Al基合金真空釬焊及接頭組織性能；分析了不同釬料對接頭界面組織和剪切強(qiáng)度的影響， 初步優(yōu)選了釬料， 優(yōu)化了釬焊連接規(guī)范參數(shù)； 利用電子探針、 掃描電鏡和X射線衍射等方法對接頭進(jìn)行了定性和定量分析。 結(jié)果表明： 采用NiCrSiB釬料連接時， 在界面處有金屬間化合物TiAl3、 AlNi2Ti和Ni基固溶體生成， TiAl3和AlNi2Ti的生成降低了接頭的剪切強(qiáng)度；采用TiZrNiCu釬料連接時， 在界面處有金屬間化合物Ti2Ni、 Ti(Cu,Al)2和Ti基固溶體生成， Ti2Ni和Ti(Cu,Al)2的形成降低了接頭的剪切強(qiáng)度；采用AgCuZn釬料連接時， 在界面處生成TiCu、 Ti(Cu,Al)2和Ag基固溶體， TiCu和Ti(Cu,Al)2 的生成是降低接頭剪切強(qiáng)度的主要原因；采用CuP釬料連接時， 在界面處生成了Cu3P、 TiCu和Cu基固溶體， Cu3P和TiCu使接頭的剪切強(qiáng)度降低； 對于NiCrSiB釬料， 當(dāng)連接溫度為1 373 K， 連接時間為5 min時， 接頭的剪切強(qiáng)度最高為219.6 MPa； 對于TiZrNiCu釬料， 當(dāng)連接溫度為1 323K， 連接時間為5 min時， 接頭的最高剪切強(qiáng)度為259.6 MPa； 對于AgCuZn釬料， 當(dāng)連接溫度為1 173 K， 連接時間為5 min時， 接頭的最高剪切強(qiáng)度為125.4 MPa； 對于CuP釬料， 當(dāng)連接溫度為1 223 K， 連接時間為5 min時， 接頭的最高剪切強(qiáng)度為98.6 MPa； 采用TiZrNiCu釬料連接Ti3Al可獲得最大接頭強(qiáng)度。
關(guān)鍵字: Ti3Al基合金；釬焊； 界面組織； 剪切強(qiáng)度
（ 1. State Key Laboratory of Advanced Welding Production Technology, Harbin Institute of Technology,
Harbin 150001, China;
2. Beijing General Research Institute of Mining and Metallurgy, Beijing 100001, China）
Abstract: The interfacial microstructure and properties of brazed joints of Ti3Al-based alloy were investigated. The effects of different brazing fillers on interfacial microstructure and shear strength were studied. And the optimum joining parameters were given. The brazed joints were qualitatively and quantitatively analyzed by means of EPMA, SEM and XRD. The results show that using brazing filler NiCrSiB, TiAl3, AlNi2Ti and Ni[s,s] are formed at the interface of joint, and the formation of Ti3Al and AlNi2Ti decreases the shear strength. Using brazing filler TiZrNiCu, Ti2Ni, Ti(Cu,Al)2 and Ti[s,s] are formed at the interface of joint, the formation of intermetallics Ti2Ni and Ti(Cu,Al)2 decreases the shear strength. Using brazing filler AgCuZn, TiCu, Ti(Cu,Al)2 and Ag[s,s] are formed, the shear strength of the joint is decreased because of the formation of TiCu and Ti(Cu,Al)2. Using brazing filler CuP, Cu3P, TiCu and Cu[s,s] are formed at the interface of the joint, the former two intermetallics decrease the shear strength. The analysis also indicates that using brazing filler NiCrSiB, the optimum brazing parameters for the joint are joining temperature T=1 373 K, joining time t=5 min, and the maximum shear strength is 219.6 MPa. To the brazing filler TiZrNiCu, the optimum parameters are temperature T=1 323 K, joining time t=5 min, and the maximum shear strength is 259.6 MPa. To the brazing filler AgCuZn, the optimum parameters are joining temperature T=1 173 K, joining time t=5 min, and the maximum shear strength is 125.4 MPa. To the brazing filler CuP, the optimum parameters are joining temperature T=1 223 K, joining time t=5 min, and the maximum shear strength is 98.6 MPa.
Key words: Ti3Al-based alloy; brazing; interfacial microstructure; shear strength
