Abstract
Friction stir back extrusion (FSBE) is a technique for lightweight metal extrusion. The frictional heat and severe plastic deformation of the process generate an equiaxed refined grain structure because of dynamic recrystallization. Previous studies proved that the fabrication of tube and wire structures is feasible. In this work, hollow cylindrical billets of 6063-T6 aluminum alloy were used as starting material. A relatively low extrusion ratio allows for a temperature and deformation gradient through the tube wall thickness to elucidate the effect of heat and temperature on the microstructure evolution during FSBE. The force and temperature were recorded during the processes. The microstructures of the extruded tubes were characterized using an optical microscope, energy-dispersive x-ray spectroscopy, electron backscatter diffraction, and hardness testing. The process reduced the grain size from 58.2 μm to 20.6 μm at the inner wall. The microhardness of the alloy was reduced from 100 to 60–75 HV because of the process thermal cycle.
| Original language | English |
|---|---|
| Pages (from-to) | 4436-4444 |
| Number of pages | 9 |
| Journal | JOM |
| Volume | 71 |
| Issue number | 12 |
| DOIs | |
| State | Published - Dec 1 2019 |
Funding
This work is supported by a lightweight-innovations-for-tomorrow (LIFT) project operated by the American Lightweight Materials Manufacturing Innovation Institute (ALMMMII), USA. The work is being conducted at Oak Ridge National Laboratory, Lockheed Martin Corporation, and the University of Notre Dame. Suhong Zhang appreciates the assistance and knowledge from Dr. Wei Tang and Dr. Zhengang Wu of ORNL for friction stir processing and metallurgy characterization. This manuscript has been authored by UT-Battelle LLC under Contract No. DE-AC05-00OR22725 with the US Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan ( http://energy.gov/downloads/doe-public-access-plan ). Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. This work is supported by a lightweight-innovations-for-tomorrow (LIFT) project operated by the American Lightweight Materials Manufacturing Innovation Institute (ALMMMII), USA. The work is being conducted at Oak Ridge National Laboratory, Lockheed Martin Corporation, and the University of Notre Dame. Suhong Zhang appreciates the assistance and knowledge from Dr. Wei Tang and Dr. Zhengang Wu of ORNL for friction stir processing and metallurgy characterization. This manuscript has been authored by UT-Battelle LLC under Contract No. DE-AC05-00OR22725 with the US Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan).
| Funders | Funder number |
|---|---|
| ALMMMII | |
| American Lightweight Materials Manufacturing Innovation Institute | |
| DOE Public Access Plan | |
| US Department of Energy | |
| UT-Battelle LLC | DE-AC05-00OR22725 |
| United States Government | |
| Lockheed Martin Corporation | |
| Oak Ridge National Laboratory | |
| University of Notre Dame |