About this Abstract |
Meeting |
MS&T23: Materials Science & Technology
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Symposium
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Additive Manufacturing of Titanium-based Materials: Processing, Microstructure and Material Properties
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Presentation Title |
Comparing Fatigue Behavior of L-PBF Samples of Nb-48%Ti Produced with Two Different Types of Powder |
Author(s) |
Fernando Landgraf, Mario Boccalini, Willy Ank Moraes, Cesar Azevedo |
On-Site Speaker (Planned) |
Fernando Landgraf |
Abstract Scope |
Cylindrical samples were produced by Laser-powder bed fusion using two types of Nb-48%Ti single phase bcc powder: a spherical powder made by Plasma Atomization (PA) and a irregular shaped powder produced by Hydrogenation-dehydrogenation (HDH). The fabrication procedure was optimized to minimize porosity, which was kept below 0.2%. As HDH samples had higher oxygen content, their yield strength was higher. After a stress relief heat treatment at 650°C, samples were milled and submitted to rotating bending fatigue tests. Twelve tests for each condition were not enough to establish a fatigue limit, due to the large variation in number of cycles to fracture at a single stress level. Microstructural analysis of the fractured surfaces has shown that cracks were initiated mostly at lack-of-fusion pores that happened to be close to the sample surface, where the stress is highest. |