Building orientation-structure-property in laser powder bed fusion of NiTi shape memory alloy

JOURNAL OF ALLOYS AND COMPOUNDS

卷:873

Article

Nematollahi, Mohammadreza¹  Saghaian, Sayed Ehsan²  Safaei, Keyvan¹  Bayati, Parisa¹  Bassani, Paola⁴  Biffi, Carlo⁴  Tuissi, Ausonio⁴  Karaca, Haluk³  Elahinia, Mohammad¹ 

[1] Univ Toledo, Mech Ind & Mfg Engn Dept, Dynam & Smart Syst Lab, 2801 W Bancroft St, Toledo, OH 43606 USA

[2] Univ Louisville, Dept Ind Engn, Louisville, KY 40292 USA

[3] Univ Kentucky, Dept Mech Engn, Lexington, KY 40506 USA

[4] CNR, Natl Res Council Italy, Inst Condensed Matter Chem & Technol Energy, ICMATE,Unit Lecco, Via Previati 1E, I-23900 Lecce, Italy

关键词: LPBF;    Additive manufacturing;    Shape memory alloy;    Thermomechanical behavior;    Build orientation;    Texture;   

DOI  :  10.1016/j.jallcom.2021.159791

来源: Elsevier

【 摘 要 】

This study is the first study on the compressive and tensile stress-strain revealing the deformation anisotropy among laser powder bed fusion NiTi parts fabricated with the same process conditions. We investigated the effects of building orientation on the microstructure and the resulting shape memory properties. To this end, three orientations were selected, namely 0, 45, and 90-degree, measured from the build plate and fabricated with the same process parameters. A strong (001) texture was formed along the building direction for all of the samples; a different texture could however be observed along the loading direction (LD). Samples fabricated with 45-degree showed a texture of (110) along the LD, as confirmed through X-ray diffraction and backscattered diffraction while 0 and 90 samples still had the (001) texture along with the LD. These texture variations created anisotropic compression-tension behaviors with deformation patterns consistent with single crystals. The (001) -textured parts showed higher strength and lower transformation strain (2.87% @ 200 MPa in tension for 0 degrees) while the (110) samples showed higher transformation strain at lower stresses (5.31% @ 150 MPa in tension for 45 degrees). (c) 2021 Elsevier B.V. All rights reserved.

【 授权许可】

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