Ben-Haroush Michael, Mittelman Brigit, Shneck Roni, Priel Elad
Department of Materials, Nuclear Research Center Negev (NRCN), Be'er-Sheva 84190, Israel.
Department of Materials Engineering, Ben-Gurion University of the Negev, Be'er-Sheva 84105, Israel.
Materials (Basel). 2023 Jan 12;16(2):769. doi: 10.3390/ma16020769.
Diffusion bonding experiments followed by tensile testing were conducted on cylindrical pairs of AA6061-AA1050 aluminum alloys. The influence of bonding time, atmosphere and surface roughness on the resulting interface strength was studied. Metallurgical characterization was performed to study the quality of the bonded interface for different process conditions, and also to investigate the process of oxide formation on the specimen surface. Finite element analysis of the bonding experiments was used to study the thermo-mechanical fields during the bonding process. Using a cohesive zone approach for modelling the bonded interface, the bond strength for the different process parameters was quantified. The results demonstrate that high bond strength can be obtained even for specimens bonded in an air furnace, provided the surface roughness is low. When the surface roughness increases, specimens bonded in air show a reduction in interface strength, which is not observed for specimens bonded in vacuum. Inspection of the bonded interface suggests that this reduction in interface strength can be attributed to oxidation and pockets of air trapped between the asperities of the contact surface, which hinder diffusion and plastic flow.
对AA6061-AA1050铝合金圆柱对进行了扩散连接实验并随后进行拉伸试验。研究了连接时间、气氛和表面粗糙度对所得界面强度的影响。进行了金相表征，以研究不同工艺条件下连接界面的质量，并研究试样表面氧化物形成的过程。连接实验的有限元分析用于研究连接过程中的热机械场。使用内聚区方法对连接界面进行建模，对不同工艺参数的结合强度进行了量化。结果表明，即使在空气炉中连接的试样，只要表面粗糙度较低，也能获得较高的结合强度。当表面粗糙度增加时，在空气中连接的试样界面强度会降低，而在真空中连接的试样则未观察到这种情况。对连接界面的检查表明，界面强度的这种降低可归因于氧化以及接触表面粗糙处之间截留的空气囊，这阻碍了扩散和塑性流动。
