【作者】 徐波；

【导师】 何景山；

【作者基本信息】 哈尔滨工业大学 ， 材料与化工（专业学位）， 2022， 硕士

【摘要】 IC10单晶高温合金作为新一代发动机叶片材料,其修复研究具有非常重要的应用价值。本论文采用瞬时液相扩散（TLP）连接对IC10合金进行修复连接工艺探究。在小间隙体系中采用丙烯酸树脂基BNi2粘带直接连接,在大间隙体系中通过冷等静压将Ni粉与BNi₂钎料粉混合制备的修复体实现了1.3mm左右间隙的连接,最后采用RRB模型利用python算法探究制备的大间隙修复体粒度分布对修复性能的影响,同时研究接头组织和力学性能演变规律及机理。BNi2粘带直接TLP修复修复小间隙IC10时,在1110℃-30min获得了50μm接头的完全等温凝固,结合界面从左到右依次为IC10/DZ/ISZ/DZ/IC10,剪切强度达到581MPa,断口呈典型的韧性断裂。所用的BNi₂粘带钎料的钎料含量约为95%,有机物在420℃完全分解,不会对IC10接头产生任何有害影响。填缝实验表明随着修复间隙的增加,接头组成相越来越复杂且伴随针状Cr B脆性有害相生成,等温凝固区所占焊缝比例越来越低,很难实现等温凝固。为了实现大间隙修复的等温凝固,在BNi₂中加入Ni粉将大间隙拆分成小间隙,通过调整工艺参数实现Ni粉间隙间的等温凝固。将Ni粉和BNi₂钎料粉按一定比例混合后通过常温静压在冷等静压200MPa、3min获得1.3mm左右的修复体,通过调控TLP温度、保温时间、Ni与BNi₂的比例、粉末粒度这四个工艺参数实现了1.3mm左右间隙的成功修复接头完好无缺陷,剪切强度可达545MPa。修复接头从左到右依次为IC10/DZ/DZ+ISZ/DZ/IC10,修复区内部Ni粉之间的结合富Cr-W的骨架状Cr B、γ-Ni和富Ni的Ni₃B三元共晶中镶（冷却凝固区）嵌着富Cr、Fe、W等溶质的镍基固溶体（等温凝固区）。明确了大间隙修复最佳工艺参数为1150℃-50min-Ni:BNi2=70:30-Ni粉800目以下。粉体粒度的改变使得大间隙修复性能大规模提升,为了研究粉体粒度分布对修复体性能的影响,首先用标准检筛器获得各个粉体群的粒级分布特征,利用python两种数学原理计算方法结合RRB模型获得其的特征粒径De和均匀性系数n。结合孔隙率、硬度、最佳工艺参数下焊后剪切强度分析得到修复性能只与颗粒群整体粗细程度有关（De=15μm以下）,整体粒度分布范围宽窄的影响不明显（均匀性系数n）。并通过满足一定粒径范围分布的两种典型级配模型:Andreasen分布模型（392MPa）和Horsfield堆积模型（566MPa）的大间隙TLP实验证实了计算结论且大直径颗粒的过量掺加会带来性能的明显下降。更多还原

【Abstract】 As a new generation of aero-engine blade material,IC10 single crystal superalloy has very important application value in connection repair research.In this topic,transient liquid phase diffusion（TLP）connection was used to explore the repair bonding process of IC10 alloy.In the small gap system,acrylic resin based BNi₂ adhesive tape is used for direct connection.In a large gap system,the composite prepared by mixing Ni powder with BNi₂ solder powder by cold isostatic pressing achieved a clearance of about 1.3mm.Finally,RRB model and Python algorithm were used to explore the influence of particle size distribution on repair performance.The joint is characterized by microstructure and mechanical properties.The complete isothermal solidification of the 50μm joint was obtained at1110℃-30min.The bonding interface was IC10/DZ/ISZ/DZ/IC10 from left to right.The shear strength reached 581MPa,and the fracture was typical ductile fracture.The BNi₂bonding solder used has a solder content of about 95%,and the organic matter completely decomposes at 420℃without any harmful effect on the IC10 joint.The experimental results show that with the increase of the repair gap,the composition phase of the joint becomes more and more complex,accompanied by the formation of brittle and harmful phase of needle-like Cr B,and the proportion of isothermal solidification zone in the weld becomes lower and lower,making it difficult to achieve isothermal solidification.In order to achieve isothermal solidification of large gap repair,Ni powder was added into BNi₂ to separate large gap into small gap,and isothermal solidification of Ni powder gap was realized by adjusting process parameters.After mixing Ni powder and BNi₂ solder powder in a certain proportion,1.3mm of filler metal was obtained by static pressing at room temperature and cold isostatic pressing at 200MPa for 3min.By adjusting the four technological parameters such as TLP temperature,holding time,ratio of Ni to BNi₂ and powder particle size,the successful repair joint with a clearance of about 1.3mm was intact and without defects.The shear strength can reach 545MPa.The repair joint is IC10/DZ/DZ+ISZ/DZ/IC10 from the right,and the combination of Ni powder in the repair area includes cr-W-rich skeleton Cr B,γ-Ni and Ni-rich Ni₃B ternary eutectic embedded（cooling and solidification zone）with Ni-rich solute（isothermal solidification zone）.The optimal process parameters of large gap repair were determined as 1150℃-50min-Ni:BNi₂=70:30-Ni800 mesh.In order to study the influence of particle size distribution on the performance of the repair body,the characteristics of particle size distribution of each powder group were obtained by using standard screening device.The characteristic particle size De and uniformity coefficient N were obtained by using python and RRB model.The results of post-weld shear strength analysis under porosity,hardness and optimum technological parameters s how that the repairing performance is only related to the overall particle size（De=less than 15μm）,and the overall particle size distribution has no obvious influence（uniformity coefficient n）.Large gap TLP experiments of two typical gradation models w ith a certain particle size distribution:the andreas distribution model（392MPa）and the Horsfield stacking model（566MPa）confirmed the calculation results,and the excessive mixing of large diameter particles would lead to a significant decline in performance.更多还原