含銅抗菌304不銹鋼有效的抗菌特性、優良的耐蝕性質和良好的加工性使其被廣為應用在食品及醫療相關器具上，其抗菌機制為基材內富銅相和病原體接觸後釋放銅離子使病原體細胞膜及蛋白等功能損失並進一步導致死亡，然而經過衝壓或拉伸等冷加工後，富銅相因機械性質小於基材而累積較高的能量，使銅在加工過程中固溶到基材內，若富銅相縮小到不足以使不銹鋼表面的鈍化膜不連續，導致銅和病原體的接觸及銅離子的釋放受到阻礙，抗菌效果也將因此消失。在形變率增加的過程中，差排等缺陷在基材內堆積，造成應變硬化，且鈍態電流密度增加，表示鈍化膜越不穩定，同時易腐蝕的富銅相減少也造成耐點蝕能力上升。
三次衝壓過後的含銅304不銹鋼在600°C熱處理30分鐘後富銅相析出成長，使銅離子釋放和抗菌能力恢復、耐點蝕能力上升，而熱處理過程中缺陷回復使硬度下降、鈍態電流密度下降；經拉伸至應變率30%後的含銅304不銹鋼在650°C熱處理40分鐘後銅離子釋放量增加最多，且耐點蝕能力下降，代表富銅相在熱處理後增加或成長，而其晶粒在熱處理時進入再結晶階段並發生析出硬化。
綜合所有研究結果，本研究探討了含銅304不銹鋼在冷加工後抗菌能力消失的機轉，再利用適當的熱處理參數成功地使抗菌能力恢復，並探討其中冷加工及熱處理參數對含銅304不銹鋼抗菌效果、銅離子釋放能力、機械性質、微結構及電化學特性的影響。

Cu-containing 304 stainless steel has effective antibacterial properties, excellent corrosion resistance, and good processability, making it widely used in food and medical instruments. Its antibacterial mechanism involves the release of Cu ions upon contact with pathogens, leading to their functional loss and death. However, during cold working, Cu dissolved into matrix and reduce the size of Cu-rich phase, which result in passive film to cover the Cu-rich phase and hindering antibacterial activity. Increasing deformation causes strain hardening and passivation film instability. After stamped Cu-304 SS heat treated at 600°C, Cu-rich phase growth restores antibacterial ability and reduces corrosion resistance. Similarly, stretched Cu-304 SS heat treated at 650°C result in enhanced Cu ion release but decreased corrosion resistance. This study investigates the loss of antibacterial ability after cold working and successfully restores it through appropriate heat treatment, analyzing the effects on antibacterial effectiveness, Cu ion release, mechanical properties, microstructure, and electrochemical characteristics of Cu-containing 304 stainless steel.

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