About this Abstract |
Meeting |
MS&T24: Materials Science & Technology
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Symposium
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Additive Manufacturing: Microstructure, Defects, and Properties
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Presentation Title |
Effects of Scanning Speed on the Shape Memory Properties of Additively Manufactured Ni-rich NiTiHf |
Author(s) |
Guher Pelin Toker, Keaton Looper, Mohammadreza Nematollahi, Saeedeh Vanaei, Mohammad Elahina , Haluk Karaca |
On-Site Speaker (Planned) |
Keaton Looper |
Abstract Scope |
Numerous studies have been conducted on NiTiHf high-temperature shape memory alloys to investigate the effects of composition, fabrication methods, and post-processing heat treatments. In this study, shape memory properties of slightly Ni-rich Ni50.4Ti29.6Hf20 (at.%) alloys fabricated via laser powder bed fusion was investigated. The laser power was kept constant at 175W, and scanning speeds were selected to be between 450 to 850 mm/s; as a result, the energy density ranged between 52 to 99 J/mm3. It was found that transformation temperatures were decreased as a function of increasing scanning speed and decreasing energy density. Austinite finish temperatures varied between 274 to 167 oC. By increasing the scanning speed, hardness values were slightly decreased from 430 to 391 HV. At higher scanning speeds, samples showed promising shape memory behavior and maximum total strain of 1.26 % was achieved for the sample fabricated with 850 mm/s scanning speed. |