In vitro degradation behavior and cytocompatibility of Mg-6Zn-0.6Si-xSn alloy

Monday, October 20, 2025: 5:00 PM
Mr. Gaurav Gupta , Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, India, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, India
Dr. Sourav Ganguly , CSIR-Institute of Minerals & Materials Technology (CSIR-IMMT), Bhubaneswar, India
Prof. Jayant Jain , Indian Institute of Technology, New Delhi, New Delhi, India
Dr. Sudhanshu Shekar Singh , Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, India
Traditional permanent biomedical implants, such as those made from titanium, cobalt, and stainless steel alloys, often necessitate secondary surgeries for removal due to their non-biodegradable nature. Magnesium (Mg) and its alloys have emerged as promising alternatives for temporary implants, offering advantages like low density, high strength-to-weight ratio, and biodegradability, closely matching the mechanical properties of human bone. Previous studies have indicated that alloying Mg with zinc (Zn), silicon (Si), and tin (Sn) enhances biocompatibility and biodegradability. However, the specific influence of Sn on the microstructure and mechanical properties of Mg-Zn-Si alloys remains underexplored.

This study investigates the processing-structure-property relationships of Mg-Zn-Si-xSn alloys with varying Sn content (x = 0, 1, 2, 3, and 4 wt.%). The type, distribution, and volume fraction of second phases present in pressure die cast alloys were identified through X-ray diffraction ,Scanning electron microscope and 3D X-ray tomography analyses. Mechanical properties were assessed via Vickers hardness testing and bulk compression tests. Subsequently, the alloys were hot-rolled up to 30% at 300°C, followed by further microstructural evaluations. Corrosion behavior was examined using potentiodynamic polarization tests, hydrogen evolution measurements, and weight loss assessments in Hanks' Balanced Salt Solution (HBSS). Post-corrosion analyses employed Raman spectroscopy, X-ray photoelectron spectroscopy (XPS),Scanning Kelvin Probe Force Microscopy (SKPFM) and SEM. Furthermore, in vitro cytocompatibility was evaluated using MG-63 osteoblast-like cells, assessing cell viability and proliferation on the corroded surfaces of the rolled alloys.

The alloy with 1 wt.% Sn demonstrated the lowest corrosion rate, signifying enhanced corrosion resistance with Sn addition. Conversely, the alloy with 4 wt.% Sn exhibited the greatest mechanical strength, but with an elevated corrosion rate. This can be corroborated with the presence of a higher amount of second phases which increase mechanical properties but also cause galvanic corrosion.

Keywords: Magnesium alloy, X-ray tomography, Biodegradability, Corrosion,HBSS

See more of: Corrosion and Environmental Degradation II
See more of: Corrosion and Environmental Degradation