(華東理工大學(xué) 機(jī)械與動力工程學(xué)院， 200237)
摘 要: 針對不同焊接參數(shù)的含鎳中間層316L不銹鋼擴(kuò)散焊接頭， 進(jìn)行室溫和550 ℃高溫拉伸實(shí)驗(yàn)， 采用SEM、 XRD和金相顯微鏡分析接頭區(qū)域的微觀結(jié)構(gòu)和相分布。 結(jié)果表明: 接頭的室溫力學(xué)性能隨焊接溫度的提高而降低， 而高溫力學(xué)性能隨溫度的提高而提高。 XRD分析表明， 焊接過程中產(chǎn)生的Fe0.64Ni0.36導(dǎo)致接頭區(qū)域的相組成不均一; 在高溫拉伸實(shí)驗(yàn)時(shí)， DB2和DB3接頭中的Fe0.64Ni0.36發(fā)生相變， 強(qiáng)度和塑性更好的FeNi3是接頭高溫強(qiáng)度提高的原因。
關(guān)鍵字: 鎳中間層; 316L不銹鋼; 擴(kuò)散焊; 高溫強(qiáng)度
diffusion bonding joints of 316L stainless steel
（School of Mechanical and Powder Engineering,
East China University of Science and Technology, Shanghai 200237, China）
Abstract: For diffusion bonding joints of 316L stainless steel with Ni interlayer bonded at different process parameters, tensile tests were performed to evaluate the strength of joints at room temperature and elevated temperature of 550 ℃. The microstructure and phase structure were identified by scanning electronic microscopy, optical microscopy and X-ray diffractometry, respectively. The results indicate that as the bonding temperature increases, the strength of joints decreases at room temperature, whereas increases at elevated temperature. The XRD analysis reveals that Fe0.64Ni0.36 produced in the diffusion bonding process results in the inhomogeneity at the bonded zone of the joints. At elevated temperature tensile tests, Fe0.64Ni0.36 of the DB2 and DB3 joints is transformed to FeNi3 with higher plasticity and strength, it is the reason for the improvement in the strength of these joints.
Key words: Ni interlayer; 316L stainless steel; diffusion bonding; high temperature strength
