Investigation of the elastocaloric effect in laser powder bed fusion NiTi porous structures

Abstract

The laser powder bed fusion (LPBF) method has been utilized to print NiTi coupons for microstructural and phase analysis. The reference part fabricated using the standard process parameters shows a strong 〈001〉 texture toward the build-up direction and the scanning directions. In this paper, we aim to develop approaches to control the crystallographic texture of the as-printed parts by wisely altering the build orientation and scanning strategy parameters. To this end, three desired orientations of 〈111〉, 〈113〉, and 〈122〉 were selected to evaluate the performance of the approaches in controlling the texture to achieve the desired dominant crystallographic orientation. The electron backscatter diffraction (EBSD) method indicates a good accuracy of the approaches in achieving the targeted textures. The X-ray diffraction (XRD) technique reveals the austenite phase as the dominant phase at room temperature in all as-printed samples. The intensity of the XRD peaks is then related to the dominant texture of each sample.