Superelasticity and compression behavior of porous TiNi alloys produced using Mg spacers

Date

2012-11-01

Author

Aydoğmuş, Tarık
Bor, Sakir

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

166
views

0
downloads

In the scope of the present study, Ni-rich TiNi (Ti-50.6 at %Ni) foams with porosities in the range 38-59% were produced by space holder technique using spherical magnesium powders as space formers. Single phase porous TiNi alloys produced with spherical pores were subjected to loading-unloading cycles in compression up to 250 MPa stress levels at different temperatures in as-processed and aged conditions. It has been observed that strength, elastic modulus and critical stress for inducing martensite decrease with increasing porosity. Partial superelasticity was observed for all porosity levels at different test temperatures and conditions employed. Irrecoverable strain was found to decrease with pre-straining and with increasing test temperature. Unlike in bulk TiNi alloys a constant stress plateau has not been observed during the compression testing of porous TiNi alloys. Instead linear superelasticity with a quite steep slope allowing 5% applied strain to be recovered after pre-straining or aging was observed. Even at test temperatures higher than austenite finish temperature in as-sintered and aged condition, strain applied could not be recovered fully. due to martensite stabilization resulting from heavy deformation of macro-pore walls and sintering necks. TiNi foams produced with porosities in the range of 38-51% meet the main requirements of biomaterials in terms of mechanical properties for use as bone implant.

Subject Keywords

Porous TiNi, Martensitic transformations, Aging, Powder metallurgy, Superelasticity

URI

https://hdl.handle.net/11511/64586

Journal

JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS

DOI

https://doi.org/10.1016/j.jmbbm.2012.05.018

Collections

Department of Metallurgical and Materials Engineering, Article

Suggestions

OpenMETU
Core

Production and characterization of porous titanium alloys Esen, Ziya; Bor, Şakir; Department of Metallurgical and Materials Engineering (2007) In the present study, production of titanium and Ti6Al4V alloy foams has been investigated using powder metallurgical “space holder technique” in which magnesium powder were utilized to generate porosities in the range 30 to 90 vol. %. Also, sintering of titanium and Ti-6Al-4V alloy powders in loose and compacted condition at various temperatures (850-1250oC) and compaction pressures (120-1125 MPa), respectively, were investigated to elucidate the structure and mechanical properties of the porous cell walls...
Microstructural characterization of hypoeutectoid steels quenched from the Ae1 - Ae3 intercritical temperature range by magnetic barkhausen noise technique Boyacıoğlu, Beril; Gür, Cemil Hakan; Department of Metallurgical and Materials Engineering (2006) This thesis aims to examine the possibility of using Magnetic Barkhausen Noise technique in characterizing the ferritic-martensitic microstructure of hypoeutectoid steels quenched from the intercritical temperature range. For this purpose, rectangular specimens were prepared from SAE 1020, 1040 and 1060 steels. The specimens were heated at different temperatures within the intercritical temperature range and then quenched into water. Microstructures of the specimens were characterized by metallographic exam...
Photoconductivity of P3HT films measured by time-resolved THz spectroscopy Esentürk, Okan; Heilweil, Edwin J. (Optical Society of America (OSA); 2007-01-01) Photoconductivities of P3HT polymer films varying in molecular weight were directly measured and compared using optical pump-THz probe spectroscopy. Conductivities of P3HT polymers depend on the polymer length, ring orientation regularity and film morphology. © 2007 Optical Society of America.
Magnetic Fe3O4-chitosan micro- and nanoparticles for wastewater treatment ŞAHBAZ, DENİZ AKIN; YAKAR, ARZU; Gündüz, Ufuk (2019-08-18) In this study, first, magnetic nanoparticles (MNP) were synthesized using a coprecipitation method and the synthesized particles were characterized using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), dynamic light scattering (DLS), and vibrating sample magnetometry (VSM). According to DLS and VSM analyses results, it was seen that the size of the MNP was smaller than 10 nm and they exhibited superparamagnetic properties, respectively. Then, magnetic Fe3O4-chitosan micro/n...
In situ DRIFTS characterization of wet-impregnated and sol-gel Pd/TiO 2 for NO reduction with CH4 Karakaş, Gürkan; Ozkan, Umit S. (Elsevier BV, 2002-05-01) The adsorption/desorption behavior of 2%Pd/TiO2 catalysts synthesized by wet-impregnation and modified sol–gel techniques were examined in NO–CH4–O2 reaction using in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The catalyst prepared by the modified sol–gel method showed significantly higher resistance toward oxygen while maintaining a 100% NO conversion. Under NO+CH4+O2 flow, the main adsorbed NO species was identified as the linearly adsorbed NO on metallic palladium (Pd0–NO)...

Citation Formats

T. Aydoğmuş and S. Bor, “Superelasticity and compression behavior of porous TiNi alloys produced using Mg spacers,” JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS, pp. 59–69, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/64586.