| Popis: |
The dissimilar materials lap-joint of Ti-6Al-4V titanium (Ti) and 6061 aluminum (Al) alloys was achieved through a metal inert gas (MIG) arc weld-brazing process. The relationships between the major MIG arc weld-brazing parameters such as travel speed of MIG torch, MIG welding current, argon flow rate of MIG torch, wettability of weld bead and mechanical property of Ti/Al lap-joint specimens were investigated. A proposed approach that integrates the Taguchi method, grey relational analysis (GRA) and fuzzy logic was employed to obtain the optimal MIG arc weld-brazing parameters. The proposed approach was adopted to solve the MIG arc weld-brazing process with multiple quality characteristics (QCs). The experimental procedure of this study not only improves the wettability of weld bead, but also increases the tensile strength of Ti/Al lap-joint specimens. Confirmation experiments revealed that this study could efficiently optimize the MIG arc weld-brazing parameters, and the average tensile strength of Ti/Al lap-joint specimens could reaches 178 MPa. During the MIG weld-brazing, higher argon flow rate of the MIG torch that produces turbulence to the weld pool and brings outside air could create a high amount of porosity over the weld bead. |
