COMPARISON OF THE WORK OUTPUT VALUES OF GRADUALLY CHANGING POROSITY SAMPLES AND THE SAMPLES WITH SINGLE PERCENT POROSITY LEVEL


Tugrul H. O. , Cakmak S., KOÇKAR B.

Proceedings of the TMS Middle East Mediterranean Materials Congress on Energy and Infrastructure Systems (MEMA 2015), Doha, Qatar, 11 - 14 January 2015, pp.201-210 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Volume:
  • Doi Number: 10.1002/9781119090427.ch20
  • City: Doha
  • Country: Qatar
  • Page Numbers: pp.201-210
  • Hacettepe University Affiliated: Yes

Abstract

In this study, the work output values and superelasticity properties of the Ni50.6Ti49.4 samples having gradually changing porosity levels were compared. Porous NiTi samples were produced with space holder technique via using pure magnesium as a space holder. Uniaxially pressed NiTi+Mg green samples were conventionally sintered under controlled atmosphere. 36 % and 80% porosity levels were combined in one sample in order to achieve gradually changing porosity, at which a shell of 18mm outer diameter of 36% was combined with 10 mm core diameter of 80% porosity. Cyclic compression tests were conducted on all 36%, 80% and 36%+80% sintered samples in order to obtain the superelastic properties. Pore architecture and microstructures of the samples were investigated to understand the transformation and superelasticity behavior of all samples. These results were then compared to come up with a suitable actuator material.