| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Environmentally Assisted Cracking: Theory and Practice
|
| Presentation Title |
Understanding the Effect of Anodic Polarization on SCC Resistance of AA6111-T8 used for Automotive Applications |
| Author(s) |
Katrina E. Catledge, Mark Nichols, Gerald S. Frankel, Jenifer S. (Warner) Locke |
| On-Site Speaker (Planned) |
Katrina E. Catledge |
| Abstract Scope |
6xxx Al-Mg-Si alloys are age-hardenable and considered resistant to stress corrosion cracking (SCC) in comparison to other age-hardened aluminum alloys. For greatest weight savings, joining of 6xxx alloys with carbon fiber reinforced polymer (CFRP) is being considered. However, galvanic coupling may reduce the SCC resistance of 6xxx alloys. This research addresses the effect of anodic polarization on the SCC resistance of AA6111-T8 to simulate galvanic coupling with CFRP. Slow rising displacement testing in 3.5 wt.% sodium chloride shows that the SCC threshold stress intensity (KTH) decreases from 16-18 MPa√m when held at the freely corroding potential (OCP), to less than 6 MPa√m at 100mVSCE above OCP. Constant stress intensity testing at OCP conditions and at applied anodic polarization levels is used to verify expected cracking behavior based on determined KTH. This work is supported by the Department of Energy under award number DE-EE0007760 through a sub-award under PPG Industries, Inc. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |