치과용 임플란트를 위한 Zr-7Cu-xSn과 Zr-7Si-xSn 합금 연구

Abstract

In order to apply the metals to bio-materials, especially dental implants, they must have high strength, corrosion resistance, and low elastic modulus and susceptibility values. To this end, the development and research of metalic bio-materials has been steadily carried out. However, there is no metalic bio-material that satisfies all conditions without side effects, so it is very important to combine and design them well in line with the increasing demand for dental implants due to the aging society worldwide. Representative metalic implant materials include pure titanium, Ti-6Al-4V, stainless steel, and CoCr alloys. However, current commercial materials have an elastic modulus that is too high compared to the bones of the human body, and are having difficulties in follow-up management due to susceptibility artifacts generated during magnetic resonance imaging (MRI) diagnosis after insertion into the human body. Therefore, in this study, we designed and manufactured a zirconium-based alloy, which is attracting attention as a bio-material, and investigated a zirconium-based alloy that prevents the problem of magnetic artificial formation and stress shielding effect and has low corrosion resistance. The Zr-7Cu-xSn (x = 1, 5, 10, 15 mass%) alloys and the Zr-7Cu-xSn (x = 1, 5, 10, 15 mass%) alloys were prepared by an arc melting process. Microstructure characterization was analyzed by microscopy and X-ray diffraction. Mechanical properties were evaluated using micro Vickers hardness and compression test. The magnetic susceptibility was evaluated using a SQUID-VSM. The average magnetic susceptibility value of the Zr-7Cu-xSn and Zr-7Si-xSn alloys were 1.17 × 10-8cm3g-1 and 1.25 × 10-8cm3g-1, as well. The corrosion tests of zirconium-based alloys were conducted through polarization test. The average Icorr value of the Zr-7Cu-xSn and Zr-7Si-xSn alloys were 0.1 ㎂/cm2 and 0.2 ㎂/cm2, as well. The elastic modulus value of the Zr-7Cu-xSn and Zr-7Si-xSn alloys were 14-25 GPa and the zirconium-based alloy is very similar to the elastic modulus value 15-30 GPa of the human bone. Consequently, the Sn added zirconium alloy, Zr-7Cu-xSn and Zr-7Si-xSn alloys are very interested and attractive as a biomaterial that reduces the stress-shielding effect caused by the difference of elastic modulus between human bone and metallic implant. In addition, it has a potential to be used metallic dental implant that effectively eliminates the artifacts in MRI images due to low magnetic susceptibility.