隨著醫療技術的持續進步，醫療材料亦不斷推陳出新。為減少二次手術對患者所造成的負擔，臨床上對骨釘材料提出具備生物可降解特性的需求。鎂合金因具有與人體骨骼相似的力學性質與密度，能有效避免傳統金屬植入物常見的屏蔽效應，因而被視為理想的生物可降解骨釘材料。然而，鎂合金在體內的降解速率過快，可能導致植入物於組織修復完成前失去支撐效果，限制其臨床應用。因此，本研究主要探討於鎂合金表面設計高熵氮化物塗層，期望在降低降解速率的同時，提升其生物相容性並增強機械性質。
本研究以密度泛函理論（Density Functional Theory, DFT）之 Vienna Ab-initio Simulation Package（VASP）第一原理計算為基礎，從材料篩選出發，結合X射線繞射分析（X-ray Diffraction, XRD）與 X 射線光電子能譜分析（X-ray Photoelectron Spectroscopy, XPS）結果，選擇適合做為鎂合金塗層的固溶高熵氮化物。進一步透過理論計算探討不同元素組成對其機械性質的影響，篩選出兼具良好生物相容性與優異耐磨耗機械特性的塗層材料。

To address the limitations of conventional metallic bone screws, particularly the need for secondary surgeries, biodegradable magnesium alloys have emerged as a promising alternative due to their favorable mechanical compatibility with human bone and excellent biocompatibility. However, the high corrosion rate of magnesium in physiological environments restricts its clinical applications. This study proposes the application of high-entropy nitride (HEN) coatings to ZK60 magnesium alloy to improve corrosion resistance and mechanical durability.
By employing first-principles calculations based on density functional theory (DFT) using the VASP package, we investigated the bulk mechanical behavior of MgZrHfTiN systems. Candidate nitride coatings were initially screened through experimental XRD and XPS analysis to ensure single-phase solid solution formation. Subsequently, compositional variations and nitrogen-defect effects were examined to evaluate their influence on hardness and elasticity.
Furthermore, we designed and analyzed interfacial models between the ZK60 substrate and rock-salt-structured HENs, focusing on lattice matching, strain compatibility, and interface energies. The results demonstrate that selected high-entropy nitrides not only enhance mechanical properties but also offer potential as wear-resistant, biocompatible coatings suitable for medical applications in biodegradable implants.

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