| About this Abstract |
| Meeting |
2019 TMS Annual Meeting & Exhibition
|
| Symposium
|
Additive Manufacturing of Metals: Fatigue and Fracture III
|
| Presentation Title |
Criticality of Porosity Defects on the Fatigue Life of Wire + Arc Additive Manufactured Titanium Alloy |
| Author(s) |
Xiang Zhang |
| On-Site Speaker (Planned) |
Xiang Zhang |
| Abstract Scope |
This study aimed at investigating the effect of internal defects on the fatigue strength of wire + arc additive manufactured titanium (WAAM Ti-6Al-4V). Unlike similar titanium alloys built by the powder bed fusion processes, WAAM Ti-6Al-4V seldom contain gas pores. However, feedstock may get contaminated and cause pores of considerable size in the built materials. Two types of specimens were tested: (1) control group without defects; (2) designed porosity specimen using contaminated wires in the specimen gauge section. Test results show that static strength of the two groups was comparable; uniform elongation was 10% (control) and 4% (porosity); fatigue strength at 10 million cycles was 600 MPa (control, maximum stress at stress ratio 0.1) and 400 MPa (porosity). Using Murakami’s approach a good correlation was found between the fatigue strength and the stress intensity factor of the crack initiating pore. Critical pore diameter was found to be between 50-100 micrometres. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |