TY - JOUR
T1 - Variation in Surface Morphology and Microstructure of 316L Biomedical Alloys Immersed in Artificial Saliva
AU - Chen, Chien Hsiu
AU - Ou, Keng Liang
AU - Wang, Wei Nan
PY - 2013
Y1 - 2013
N2 - Objective: The objective of this study was to compare changes in the surface morphology and microstructure of different types of 316L orthodontic bracket alloys such as one-piece injection molding (Group A) and two-piece soldering (Group B) that were immersed in artificial saliva solution (37 °C/pH 7.0) for various periods. Methods: An optical microscope, atomic force microscope, X-ray diffractometer, and a scanning electron microscope equipped with an energy-dispersive X-ray spectrometer were used to investigate the surface properties including microstructure, roughness, and chemical compositions. Results: The study results demonstrated that corrosion in both types of orthodontic brackets (A and B) initially occurred in the 3rd month, and an austenite (γ) → [γ + (Fe, Cr)O compound] microstructure transition occurred in the matrix of the bracket body when both orthodontic brackets were subjected to immersion for more than 3 months. Conclusion: The Group A brackets, which exhibited better surface characteristics, maintained a low and constant level of surface roughness after various immersion times. Therefore, a modified metal injection molding (MIM) process based on a thermosetting resin developed with 316L stainless steel showed fewer pores and higher corrosion resistance.
AB - Objective: The objective of this study was to compare changes in the surface morphology and microstructure of different types of 316L orthodontic bracket alloys such as one-piece injection molding (Group A) and two-piece soldering (Group B) that were immersed in artificial saliva solution (37 °C/pH 7.0) for various periods. Methods: An optical microscope, atomic force microscope, X-ray diffractometer, and a scanning electron microscope equipped with an energy-dispersive X-ray spectrometer were used to investigate the surface properties including microstructure, roughness, and chemical compositions. Results: The study results demonstrated that corrosion in both types of orthodontic brackets (A and B) initially occurred in the 3rd month, and an austenite (γ) → [γ + (Fe, Cr)O compound] microstructure transition occurred in the matrix of the bracket body when both orthodontic brackets were subjected to immersion for more than 3 months. Conclusion: The Group A brackets, which exhibited better surface characteristics, maintained a low and constant level of surface roughness after various immersion times. Therefore, a modified metal injection molding (MIM) process based on a thermosetting resin developed with 316L stainless steel showed fewer pores and higher corrosion resistance.
KW - Corrosion
KW - Metal bracket
KW - Metal injection modeling
KW - Microstructure
KW - Phase transformation
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U2 - 10.1016/j.jecm.2013.01.008
DO - 10.1016/j.jecm.2013.01.008
M3 - Article
AN - SCOPUS:84875264846
SN - 1878-3317
VL - 5
SP - 30
EP - 36
JO - Journal of Experimental and Clinical Medicine(Taiwan)
JF - Journal of Experimental and Clinical Medicine(Taiwan)
IS - 1
ER -