楊衛(wèi)鵬2，朱春玲2， 李宏偉1
( 1. 哈爾濱工業(yè)大學(xué) 現(xiàn)代焊接生產(chǎn)技術(shù)國(guó)家重點(diǎn)實(shí)驗(yàn)室， 哈爾濱 150001；
2. 西安航天發(fā)動(dòng)機(jī)廠， 西安 710061)
摘 要: 對(duì)QCr0.8與1Cr21Ni5Ti的2 mm厚平板試件進(jìn)行了等厚對(duì)中電子束焊接； 采用光學(xué)顯微鏡、掃描電鏡能譜分析方法對(duì)接頭區(qū)顯微組織及成分進(jìn)行了研究， 確定了顯微組織構(gòu)成； 根據(jù)電子束焊接的特點(diǎn)， 建立了QCr0.8與1Cr21Ni5Ti等厚對(duì)中電子束焊接接頭形成的物理模型， 并對(duì)接頭不均勻組織的形成機(jī)制進(jìn)行了探討。結(jié)果表明： QCr0.8/1Cr21Ni5Ti等厚對(duì)中電子束焊接接頭顯微組織形貌為組織及化學(xué)成分極不均勻的Cu(Fe)＋(α+ε)的鑄態(tài)混合組織，其宏觀組織可分為3個(gè)區(qū)域： 顯微組織結(jié)構(gòu)相同，均為以Cu(Fe)為主， 內(nèi)有一定數(shù)量不均勻彌散分布的α+ε相混合組織的焊縫左上部組織區(qū)及焊縫底部組織區(qū)； 以α+ε相為主， 內(nèi)有少量彌散分布的Cu(Fe)顆粒混合組織的焊縫中部組織區(qū)； 接頭組織的形成是由接頭金屬熔化及匙孔形成階段， 接頭凝固的初期階段（析出γ＋ε相， 并形成3個(gè)區(qū)域），接頭凝固的中期階段（γ＋ε相結(jié)晶完成）， 接頭凝固的后期階段（形成Cu(Fe)相， 焊縫完全變?yōu)楣虘B(tài)）， 接頭凝固的最終階段（元素?cái)U(kuò)散及γ→α相變， 形成最終組織）聯(lián)合作用的結(jié)果。
關(guān)鍵字: 鉻青銅； 雙相不銹鋼； 電子束焊接； 組織形成
of QCr0.8 and 1Cr21Ni5Ti
WU Lin1,YANG Wei-peng2, ZHU Chun-ling2, LI Hong-wei1
（ 1. State Key Laboratory of Advanced Welding Production Technology,Harbin Institute of Technology, Harbin 150001, China；
2. Xi’an Space Engine Factory,
Xi’an 710061, China）
Abstract: The electron beam welding was made on 2 mm-thick Qcr0.8 and 1Cr21Ni5Ti. The microstructural characteristics and compositions were investigated by optical microscope and scanning electron microscope. The actual microstructural characteristics were identified. According to the characteristics of the electron beam welding, a physical model was built about electron beam welding joint formation mechanism on the equal thick Qcr0.8 and 1Cr21Ni5Ti. The formation mechanism of unhomogeneous joint structure was discussed. The results show that microstructure of QCr0.8/1Cr21Ni5Ti joint consists of Cu(Fe)＋(α+ε) casting mixed structures, which are very unhomogeneous in microstructure and chemical composition. The macrostructure can be divided into three parts. There are alike microstructure zones at the bottom of the joint and top near QCr0.8, which consist of Cu(Fe) dispersed of some discrete unhomogeneous α+ε. There is α+ε zone with little discrete Cu(Fe) at the middle of the joint. The joint microstructure is formed through five phases: the metal melting and keyhole forming phase, the initial solidifing phase(γ＋ε) is separated out and three zones are shaped in this phase), the medial solidifing phase(γ＋ε crystallization), the upper solidifing phase(Cu(Fe) is formed and joint is solidified) and the terminative solidifing phase(elements diffusing, γ→α phase transformation， final microstructure formed).
Key words: Qcr0.8; 1Cr21Ni5Ti; electron beam welding; microstructure formation
