About this Abstract |
| Meeting |
2025 AWS Professional Program
|
| Symposium
|
2025 AWS Professional Program
|
| Presentation Title |
Effect of Inoculants on the Microstructure and Strength of Aluminum Alloy 6061 Welds
AWS/FABTECH 2025 |
| Author(s) |
Brett Tucker Tucker Roper, Jonah Duch, Jack Herrmann, Austin Pisani |
| On-Site Speaker (Planned) |
Brett Tucker Tucker Roper |
| Abstract Scope |
Aluminum alloy 6061 (AA6061) is a popular aluminum alloy commonly selected for its high strength structural properties. However, it has poor weldability and is particularly susceptible to solidification cracking. Currently, the main method of laser welding AA6061 is to use a filler metal like AA4047, but this lowers the strength of the welded joint and limits AA6061’s usefulness as a lightweighting material. Recent work has shown that solidification cracking of AA6061 during laser welding can be avoided by adding in boron carbide and titanium inoculants. A viable AA6061 laser weld with no filler metal allows for many more manufacturing design possibilities that have previously been a challenge.
Our hypothesis is that while this inoculated AA6061 joint will be stronger than the weaker AA4047 weld, the ceramic and intermetallic inoculant particles will reduce the toughness. To investigate this, the microstructure and tensile behavior of welded samples of inoculated AA6061 were characterized. Inoculants were added to the weld joint through welding to a butter layer with wire directed energy deposition (W-DED) or via cold spray into the joint. With cold spray, the inoculant loading was varied to determine the effect of inoculant loading on strength and microstructure. After welding, partial weld penetration tensile testing was performed. Electron and optical microscopy were used to study the microstructure. Fractography was performed to determine what role inoculants played on final failure.
Partial weld penetration tensile testing is a useful method to determine the actual strength of the welded joint. Welded AA6061-AA4047 and crack-free AA6061-AA6061 samples were compared to inoculated and welded AA6061. These inoculated samples were fabricated with different deposition technique (cold spray or W-DED), different inoculant loadings, and different welding procedures. The grain size, inoculant loading, and overall microstructure of these samples were also measured and correlated to the tensile data. |
| Proceedings Inclusion? |
Undecided |