本研究利用多元素粉末熱壓燒結靶（單一粉末顆粒內含 Al、Cr、Nb、Si、Ti 五種元素）以及鉬與鉭純金屬電弧熔煉靶，成功製備七元高熵合金鍍層 (AlCrNbSiTiMoTa)。透過調整氮氣通量 (0 ~ 25 sccm)，鍍層依序命名為 RN0、RN10、RN15、RN20 及 RN25，並研究不同氮通量對鍍層結構的影響，進一步分析其機械性質、磨潤特性及抗腐蝕性能。為模擬 Inconel 718 鎳基合金切削過程中的高溫環境，鍍層經 950°C、1 小時的真空退火處理，退火後分別命名為 HRN0、HRN10、HRN15、HRN20 及 HRN25，以探討鍍層的熱穩定性。研究結果顯示，RN10 鍍層呈現非晶結構，而其餘鍍層均為 FCC 結構。經退火後，所有鍍層皆維持 FCC 結構。其中，RN15 鍍層在退火前表現出最佳的硬度與磨潤性能，且退火後硬度、附著性與磨潤性能皆進一步提升，主要歸因於退火後鍍層結構的緻密化提升了其強度。此外，本研究進一步探討中介層對 RN15 鍍層的影響，發現改用 Cr 中介層的 RN15-Cr 鍍層在附著性(>100N)與磨潤性能(1.76μm, 9.12×10⁻⁶ mm³/Nm)方面有顯著突破。然而，退火後的 HRN15-Cr 鍍層在硬度、附著性及耐磨耗性能均大幅下降，顯示其熱穩定性較差。在 Inconel 718 鎳基合金的銑削實驗中，分別使用裸刀、RN15 及 RN15-Cr 鍍層刀具進行測試。結果顯示，RN15-Cr 鍍層刀具的表現明顯差於其他兩者，與其較差的熱穩定性結果一致。而 RN15 鍍層刀具在完成 18 m 銑削實驗後，刀腹磨耗相較於裸刀減少 31.4%，證實 RN15 鍍層具有一定的刀具保護作用，能有效延長刀具壽命。

A seven-element high-entropy alloy coating (AlCrNbSiTiMoTa) was deposited using a sintered multi-element powder target (Al, Cr, Nb, Si, Ti in one particle) and arc-melted Mo and Ta targets. By varying nitrogen flow (0–25 sccm), coatings RN0–RN25 were obtained. Their structure, mechanical properties, tribological behavior, and corrosion resistance were studied. To simulate high-temperature machining of Inconel 718, coatings were vacuum-annealed at 950 °C for 1 hour, renamed HRN0–HRN25. RN10 showed an amorphous structure, while others retained an FCC phase before and after annealing. RN15 showed the best pre-annealing hardness and tribological performance, which further improved post-annealing due to densification. Adding a Cr interlayer (RN15-Cr) enhanced adhesion and wear resistance, but post-annealing (HRN15-Cr) led to significant degradation, indicating poor thermal stability. Milling tests on Inconel 718 showed RN15-coated tools outperformed both uncoated and RN15-Cr-coated tools. RN15 reduced flank wear by 31.4%, confirming its durability and protective effectiveness.

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