(清華大學 機械工程系 教育部先進成形制造重點實驗室，北京 100084)
摘 要: 用熱−力學模擬試驗機Gleeble 1500D進行O相合金Ti-22Al-25Nb的固態(tài)擴散連接。結(jié)果表明：當連接溫度和連接壓強分別不低于970 ℃和7 MPa以及保溫時間不短于30 min時，能獲得界面結(jié)合致密的接頭；當連接溫度高于1 000 ℃時，B2基體相明顯粗化，且O相明顯減少；當連接溫度、壓強和保溫時間分別為1 020 ℃、7 MPa和30 min時，接頭室溫和650 ℃的拉伸強度分別為925 MPa和654 MPa；當連接溫度不高于1 000 ℃的接頭，拉伸斷裂大部分發(fā)生在結(jié)合界面；當連接溫度高于1 000 ℃時，則斷裂主要發(fā)生在近界面母材中。
關(guān)鍵字: O相合金；擴散連接；界面結(jié)合；接頭強度
（Department of Mechanical Engineering, Key Laboratory for Advanced Manufacturing by Materials Processing Technology, Ministry of Education of China, Tsinghua University, Beijing 100084, China）
Abstract:The solid diffusion bonding of Ti-22Al-25Nb O phase alloy was performed with a thermal-mechanical simulator Gleeble 1500D. The results show that a tight bonding interface is formed under conditions of the bonding temperature higher than 970 ℃, bonding pressure higher than 7 MPa and holding time longer than 30 min. When the bonding temperature is higher than 1 000 ℃, the interfacial matrix phase B2 is coarsened and increased, while the amount of O phase is decreased. The tensile strengths at room temperature and 650 ℃ of the joints under conditions of bonding temperature 1 020 ℃, bonding pressure 7 MPa and bonding time 30 min reach up 925 and 654 MPa, respectively. The tensile fracture of joints mostly occurs at the bonding interfaces when the bonding temperature is lower than 1 000 ℃, while the tensile fracture of joints mostly occur in base materials near the bonding interfaces when the bonding temperature is higher than 1 000 ℃.
Key words: O-phase alloy; diffusion bonding; interfacial bonding; joint strength
