抗菌不銹鋼是一種額外添加抗菌元素的不銹鋼種類，常見的抗菌元素包含銀與銅兩種，而銅相比銀的成本更為低廉，因此目前市面上多為含銅系列的抗菌不銹鋼。由於抗菌不銹鋼除了有美觀及良好耐蝕性質，同時表面又具備抗菌效果，因此在食品與醫療相關領域上具有極高的應用價值。然而，目前抗菌不銹鋼大多採用熔煉法將銅元素混合至不銹鋼材內，使整個鋼材均具備抗菌效果，但添加成本較高的銅會使生產單價提高，且鋼材的性能也會發生改變。由於抗菌效果僅發生在鋼材表面，是否需要整體鋼材均具備抗菌效果成為值得新考的問題，因此本研究開發一種新的製程使不銹鋼表面形成銅合金化層，使其在不改變基材的性能下鋼材表面又可產生抗菌效果。
在大氣環境對鍍銅SS440C進行熱處理後，從EDS分析發現表面銅層發生氧化，代表排除氧的影響是重要的製程條件，因此試片需在保護氣氛或真空環境下進行熱處理。後續採用真空封管將試片密封並熱處理後，證明能有效的隔絕大氣的影響，然而從EDS分析上均無法在SS440C表面辨別出Cu訊號，代表Cu在SS440C的溶解度極低。為了提高Cu在基板的溶解度，透過Ni均能對Cu與Fe互溶的特性，挑選Ni作為滲銅輔助劑。對Cu-Ni-SS440C試片熱處理後，從EDS能在SS440C表面辨別出明顯的Cu訊號。透過調整實驗參數後顯示鎳層厚度、持溫時間與溫度均會對滲銅行為產生影響，且目前可得到的最大滲銅深度約70 μm。而從XRD分析顯示當Ni擴散至基材內部時，會造SS440C的基地由BCC結構轉變為FCC結構，使基材對Cu的溶解度提高，也代表Ni的擴散行為會主導滲銅的效果。而在含銅量為10 wt.%的合金層表面進行抗菌測試後，顯示抗菌率可達99.50%。
綜合實驗結果，通過使用Ni作為滲銅輔助劑後，本研究成功對SS440C表面製備含銅合金層，其原理是透過Ni使SS440C基地產生FCC相變，而提高基材對Cu的溶解度。從該原理來看，顯示此技術可應用於大部分的肥粒鐵系不銹鋼，且可依據使用場合，通過製程參數調整來控制預期的滲銅深度，且經由抗菌測試得知滲銅表面能產生抗菌效果，證實該技術能有效地使鋼材表面產生抗菌效果。

Antibacterial stainless steel is one kind of the stainless steel which contain the Cu element to form antibacterial performance. At present, most of the antibacterial stainless steel is manufactured by the melting process. However, adding the high cost of copper increases its production price. Since the antibacterial effect only occurs on the surface, this research developed a new process to form a copper-containing alloy layer on the steel surface. This technique not only can form an antibacterial surface on the steel and without changing substrate mechanical properties.
After heated the Cu-plated SS440C in an atmospheric environment, the (EDS) analytical result shows that the copper layer is oxidized. It means the specimen must be protected in an inert atmosphere or a vacuum environment to prevent oxidization.
The XRD result proved that the vacuum seal process is effective to isolates specimen from atmosphere. However, after heated the Cu-plated SS440C, the EDS result shows there is no Cu signal can be detected on the SS440C surface. It means the solubility of Cu is too low to solute inside the SS440C. Because Ni has high solubility with Cu and Fe, Ni is selected as a copper-infiltration agent to let the Cu diffuse into the substrate. We found that the heated Cu-Ni-SS440C specimen significantly contains Cu element due to its EDS signal. The diffusion depth of Cu is influenced by the thickness of Ni layer, the holding temperature and time during heating process. Especially, this work was able to produce Cu-Ni-SS440C with 70 μm Cu alloy layer. Additionally, the XRD results indicates that α-Fe is changed to be γ-Fe due to the Ni diffusion into the SS440C matrix, causing a corresponding increase of Cu solubility. It is also found that the Cu diffusion is subjected to the variation of Ni diffusion rate and concentration.
Based on the experimental results, this study successfully prepared a copper-containing alloying layer on the SS440C surface by using Ni as a copper infiltration agent. The mechanism is caused by γ transformation due to Ni diffuses into the SS440C, then increasing the solubility of the Cu. It also means that this technology can be applied to most ferrous iron-based stainless steels, and the expected copper diffusion depth can be controlled by adjusting the parameters of the process according to the application. The antibacterial test showed the alloyed layer with a Cu content 10 wt.% can reach 99.50% of antibacterial rate, which proves that the technology can produce an antibacterial alloy on the steel surface.

[1] 赵栄达、高崭、孙乐兵和张伟强，"1Cu13Cu1.5的微觀組織和性能"，金屬功能材料，第13卷，第6期，第18-21頁，2006年。
[2] 王帅、王忠林、杨春光、卢志江和杨柯，"3Cr13MoCu型馬氏體抗菌不銹鋼的研發"，第九屆中國抗菌產業發展大會論文集，第300-308頁，2019年。
[3] L. Nan, W. Yang, Y. Liu, H. Xu, Y. Li, M. Lu and K. Yang, "Antibacterial mechanism of copper-bearing antibacterial stainless steel against E. coli," J. Mater. Sci. Technol., vol. 24, pp. 197-201, 2008.
[4] 刘永前、南黎、陈德敏和杨柯，"含銅馬氏體抗菌不銹鋼的研究"，稀有金屬材料與工程，第37卷，第8期，第1380-1383頁，2008年。
[5] 南黎、刘永前、吕曼祺和杨柯，"抗菌不锈钢中的富铜析出相的杀菌作用研究"，世界鋼鐵，第9卷，第2期，第49-51頁，2009年。
[6] M. McGuire, Stainless Steels for Design Engineers USA: ASM International, 2018.
[7] H. Baker and H. Okamoto, ASM Handbook: Alloy Phase Diagrams. USA: ASM International, Materials Park, Ohio, 1992.
[8] T. G. Gooch, "Welding martensitic stainless steels," Welding Institute Research Bulletin, 1977.
[9] H. E. Mcgannon, The Making, Shaping, and Treating of Steel, 9th ed. Pittsburgh: U.S. Steel Corporation, 1971.
[10] Z. Nishiyama, Martensitic transformation. the USA: Academic Press Inc., 1978.
[11] 黃振賢，金屬熱處理，第一版，台灣新北市：文京圖書，2014年。
[12] 黃振賢，機械材料，第二版，台灣新北市：新文京開發，2004年。
[13] 陳鴻賓譯，"不鏽鋼的耐腐蝕性"，防蝕工程，第6卷，第1期，第44-60頁，1992年。
[14] J. C. Lippold and D. J. Kotecki, Welding metallurgy and weldability of stainless steels. 2005.
[15] J. A. Lemire, J. J. Harrison, and R. J. Turner, "Antimicrobial activity of metals: mechanisms, molecular targets and applications," Nature Reviews Microbiology, vol. 11, pp. 371-384, 2013.
[16] K. D. Karlin, "Metalloenzymes, structural motifs, and inorganic models.," Science, vol. 261, pp. 701-708, 1993.
[17] D. A. Rowley and B. Halliwell, "Superoxide-dependent and ascorbate-dependent formation of hydroxyl radicals in the presence of copper salts: a physiologically significant reaction?," Archives of Biochemistry and Biophysics, vol. 225, no. 1, pp. 279-284, 1983.
[18] Y. Yoshida, S. Furuta, and E. Niki, "Effects of metal chelating agents on the oxidation of lipids induced by copper and iron," Biochimica et Biophysica Acta (BBA)-Lipids and Lipid Metabolism, vol. 1210, no. 1, pp. 81-88, 1993.
[19] G. Grass, C. Rensing, and M. Solioz, "Metallic copper as an antimicrobial surface," Applied and environmental microbiology, vol. 77, no. 5, pp. 1541-1547, 2011.
[20] L. Macomber and J. A. Imlay, "The iron-sulfur clusters of dehydratases are primary intracellular targets of copper toxicity," Proceedings of the National Academy of Sciences, vol. 106, no. 20, pp. 8344-8349, 2009.
[21] Z. G. Dan, H. W. Ni, B. F. Xu, J. Xiong, and P. Y. Xiong, "Microstructure and antibacterial properties of AISI 420 stainless steel implanted by copper ions," Thin solid films, vol. 492, no. 1-2, pp. 93-100, 2005.
[22] L. Nan, Y. Liu, M. Lü, and K. Yang, "Study on antibacterial mechanism of copper-bearing austenitic antibacterial stainless steel by atomic force microscopy," Journal of Materials Science: Materials in Medicine, vol. 19, no. 9, pp. 3057-3062, 2008.
[23] I. Hong and C. H. Koo, "Antibacterial properties, corrosion resistance and mechanical properties of Cu-modified SUS 304 stainless steel," Materials Science and Engineering: A, vol. 393, no. 1-2, pp. 213-222, 2005.
[24] T. Xi, M. B. Shahzad, D. Xu, Z. Sun, J. Zhao, C. Yang, M. Qi and K. Yang, "Effect of copper addition on mechanical properties, corrosion resistance and antibacterial property of 316L stainless steel," Materials Science and Engineering: C, vol. 71, pp. 1079-1085, 2017.
[25] 向红亮、范金春、刘东、郭培培和颐兴，"抗菌时效处理对含Cu双向不锈钢组织和性能影响"，金属学报，第48期，第1081-1096頁，2012年。
[26] F. Luo, Z. Tang, S. Xiao, and Y. Xiang, "Study on the performance of new process for treating copper-containing antibacterial stainless steel," Materials Research Express, vol. 6, no. 4, p. 046554, 2019.
[27] L. Ren, K. Yang, L. Guo, and H.-w. Chai, "Preliminary study of anti-infective function of a copper-bearing stainless steel," Materials Science and Engineering: C, vol. 32, no. 5, pp. 1204-1209, 2012.
[28] T. Velikanova and M. Turchanin, "Chromium-Copper-Iron," Landolt Börnstein, vol. 11, p. 88, 2008.
[29] Y. Z. Wan, S. Raman, F. He, and Y. Huang, "Surface modification of medical metals by ion implantation of silver and copper," Vacuum, vol. 81, no. 9, pp. 1114-1118, 2007.
[30] 塑膠及非多孔表面抗菌性測定法, C. N. Standards, Taiwan, 2015.
[31] Antibacterial products - Test for antibacterial activity and efficacy, J. S. Association, 2010.
[32] Measurement of antibacterial activity on plastics and other non-porous surfaces, ISO, 2011.
[33] M. Schlesinger and M. Paunovic, Modern electroplating. John Wiley & Sons, 2011.
[34] 賴耿陽譯著，電鍍技術 (工業叢書)，台灣臺南巿：復漢出版社，1986年.
[35] 白蓉生，電鍍教程 (科學圖書大庫)，台灣臺北巿：徐氏基金會，1981年.
[36] 王大倫，實用電鍍學 (科學圖書大庫)，台灣臺北巿：徐氏基金會，1978年.
[37] A. Handbook, Volume 5: Surface Engineering (Electroless Nickel Plating). 1994, pp. 290-305.
[38] D. R. Gaskell, S. Scholl, Ed. Introduction to the thermodynamics of materials, 5 ed. USA: Taylor&Francis, 2008.
[39] 成丽丽和董颐，"高碳, 高合金铁基渗铜烧结阀座材料"，北京科技大学学报，第21卷，第1期，第44-47頁，1999年。
[40] 王林山、汪礼敏、徐景杰和张景怀，"渗铜剂成分对烧结钢渗铜性能的影响"，粉末冶金材料科學與工程，第15卷，第5期，第500-504頁，2010年。
[41] 王世森、许伯藩、倪红卫和熊平源，"渗铜法制备抗菌不锈钢渗层工艺的研究"，金属热处理，第28卷，第2期，第49-51頁，2003年。
[42] V. Raghavan, "Phase Diagram Updates and Evaluations of the Al-Fe-P, B-Fe-U, Bi-Fe-Zn, Cu-Fe-Zn, Fe-Si-Zn and Fe-Ti-V Systems," Journal of phase equilibria and diffusion, vol. 34, no. 3, pp. 230-243, 2013.
[43] C. Wang, X. Liu, L. Zhang, and K. Ishida, "Aluminium-Copper-Iron," Landolt-Bornstein, New Series IV/11A2, edited by G. Effenberg and S. Ilyenko (Springer-Verlag, Berlin, Heidelberg, Germany, 2005), p. 1, 2005.
[44] V. Raghavan, "Cu-Fe-Mn (copper-iron-manganese)," Journal of phase equilibria and diffusion, vol. 30, no. 4, pp. 381-383, 2009.
[45] I. Gallino, S. Curiotto, M. Baricco, M. E. Kassner, and R. Busch, "Homogenization of highly alloyed Cu-Fe-Ni: a phase diagram study," Journal of Phase Equilibria and Diffusion, vol. 29, no. 2, pp. 131-135, 2008.
[46] R. Colás and G. E. Totten, Encyclopedia of iron, steel, and their alloys (Online version). CRC Press, 2016.