Abstract
Self-powered brazing of Ti-6Al-4V was performed using Ni/Al reactive multilayer films (RMFs) as self-propagated heat resources. BAlSi-4 was first coated on Ti-6Al-4V by plasma welding, then alternating layers of Ni and Al were successfully deposited on BAlSi-4 up to 32.9 μm thick with e-beam deposition. The joint microstructure was investigated and the AlNi and Ni5Al3 phases were identified in the RMF. The cause for the two phases was determined to be differences in the diffusivity of Ni and Al, ultrafast brazing time, and faster cooling at the interface between brazing filler metal and the RMF. The maximum temperature of 683 °C was reached in the brazed joint, with a total RMF thickness of 135 μm, which is more than sufficient tomelt the BAlSi-4 brazing material. The maximum bonding strength obtained was 10.6 MPa, with a self-power brazing procedure conducted in a minute. It is possible to further improve the bonding strength by using more ductile RMFs and/or modifying the bonding interface configuration.
| Original language | English |
|---|---|
| Article number | 985 |
| Journal | Applied Sciences (Switzerland) |
| Volume | 8 |
| Issue number | 6 |
| DOIs | |
| State | Published - Jun 15 2018 |
Funding
Institute of Technology, the National Aeronautics and Space Administration (NASA) and a Department of Energy (DOE) Office of Science User Facility project at the Center for Nanophase Materials, Oak Ridge National ALacbkonroawtolreyd.gments: We also acknowledge John Dunlap, Maulik Patel, and the Joint Institute of Advanced Materials for use of their electron microscopy, EDX, and X-ray diffraction equipment and the training Acknowledgments: We also acknowledge John Dunlap, Maulik Patel, and the Joint Institute of Advanced Materials for use of their electron microscopy, EDX, and X-ray diffraction equipment and the training they Conflicts of Interest: The authors declare no conflict of interest. provided. We also acknowledge John Dunlap, Maulik Patel, and the Joint Institute of Advanced Materials for use of their electron microscopy, EDX, and X-ray diffraction equipment and the training they provided. This project is jointly supported by a subcontract with the Jet Propulsion Laboratory/California Institute of Technology, the National Aeronautics and Space Administration (NASA) and a Department of Energy (DOE) Office of Science User Facility project at the Center for Nanophase Materials, Oak Ridge National Laboratory.
Keywords
- Brazing
- Nanolayers
- Reactive bonding
- Reactive multilayer
- Self-powered
- Titanium