Novel Mri-Compatible Zr-Mo-Nb Alloys with Superior Mechanical Performance, High Corrosion Resistance and Good Cytocompatibility for Biomedical Applications

Abstract

Nowadays, MRI diagnostics have become indispensable in modern medicine, and the development of MRI-compatible materials is an urgent requirement for both modern medicine and materials science. Herein, MRI-compatible Zr-Mo-Nb alloys were developed by plasma arc melting and hot rolling process for biomedical applications. The Nb addition induces the composition segregation, b phase precipitations, and significant grain refinements in Zr-1Mo-xNb alloys, thereby contributing to an ultrafine a+b lamellar structure in hot-rolled (HRed) Zr-1Mo-3Nb alloys. Thanks to the nano-sized a+b lamellar structure, a high yield strength (YS) of 819.6 ± 20.9 MPa and an acceptable elongation of 11.8 ± 1% were realized in the HRed Zr-1Mo-3Nb alloy. Additionally, the incorporation of Nb with a high PB ratio and a relatively high equilibrium potential in the Zr-1Mo matrix enhances the stability of the passivation layer, leading to a more positive corrosion potential. Consequently, this significantly improves the corrosion resistance of HRed Zr-1Mo-xNb alloys.  Notably, the Zr-1Mo-3Nb alloy exhibits lower magnetic susceptibility than the Zr-1Mo alloy, indicating improved MRI compatibility. These findings highlight the potential of the MRI-compatible Zr-1Mo-3Nb alloy as a promising material for implants and devices in MRI environments, offering superior mechanical performance, high corrosion resistance, and good cytocompatibility.

Keywords: Zr-based alloy, Microstructural Evolution, mechanical properties, MRI compatibility.