对DD407/FGH95合金系进行了1120c/120MPa/3h,1170℃/120MPa/3h和1210℃/120MPa/3h3个工艺参数下的热等静压扩散连接实验,实验分析互扩散区元素分配规律与计算结果基本吻合,验证了利用DICTRA与Thermal-Calc软件结合计算扩散连接界面元素分布情况的准确性.进而给出了利用元素和相分布模拟结果对实验进行预测的依据,提出扩散连接温度应在1170—1200℃之间选择,可避免界面大γ'相出现.结合理论计算和实验分析,建立了粉末高温合金与单晶高温合金HIP扩散连接工艺选择原则.
Manufacturing dual superalloy turbine rotor is becoming an important direction of development in the field of aviation and aerospace. In order to improve working temperature and service life of turbine rotor, blade materials have been evolved to single crystal superalloys, turbine disc materials have also been developed to powder superalloys. Therefore the connection of these two materials has become key problem in improving turbine performance. Nowadays hot isostatic pressure (HIP) bonding is a preferable bonding technique due to no fusion and macroscopic deformation in bonding area. In HIP bonding process, elements diffusion is the key factor in forming microstructure of interface, and determining interfacial properties. At present, articles about HIP diffusion bonding mainly focused on interfacial microstructure and mechanical test of bonding couples, while few articles explored the relationship between elements diffusion and microstructure forming. In this work, diffusion couples of DD407 and FGH95 alloys were conducted under 1120, 1170, 1210 E and 120 MPa HIP for 3 h, the microstructure and elements distribution of interface were studied to verify simulated results in the last article, and explore interface formation mechanism. Then the relationship between simulated phase distribution and actual microstructure of interface was built, which can be used to forecast interface morphology. And also the recrystallization in bonding zone was studied. Combining simulated and experimental results, this work put forwards principles for HIP bonding process controlling.