| About this Abstract |
| Meeting |
MS&T22: Materials Science & Technology
|
| Symposium
|
Additive Manufacturing of Titanium-based Materials: Processing, Microstructure and Material Properties
|
| Presentation Title |
Effect of Surface Finish on Fatigue Behavior of Laser Powder Bed Fusion Processed Hydride-Dehydride Ti-6Al-4V Powder |
| Author(s) |
Mohammadreza Asherloo, Ziheng Wu, Muktesh Paliwal, Anthony Rollett, Amir Mostafaei |
| On-Site Speaker (Planned) |
Mohammadreza Asherloo |
| Abstract Scope |
Non-spherical hydride-dehydride Ti-6Al-4V powder with particle size distribution of 50-120 μm is used for additive manufacturing parts using optimum processing parameters in laser powder bed fusion to achieve a relative density of >99.9%. Microstructural observations are performed and show a columnar and equiaxed grain structure in vertical and horizontal cross-sections, respectively. Surface roughness measurement show an average roughness of Ra = 15.71±3.96 μm in the as-build specimens, while the mechanically ground surfaces show an average roughness of Ra = 0.19±0.04 μm. Fatigue tests results show comparable fatigue life with spherical powders, and fractography analyses show crack initiation from the rough surface in the as-built specimens, while the subsurface defects in the mechanically ground specimens are responsible for crack initiation and failure. μ-CT results show transition of inner large pores to subsurface region after the mechanical griding, which acts as stress concentrators and decrease fatigue life of mechanically ground samples under high stress amplitude. |