本實驗主要是在研究釩V的含量對CoCrFeNiVx高熵合金的微結構及腐蝕性質的影響，這三種合金的成分分別是CoCrFeNiV0.2、CoCrFeNiV0.5和CoCrFeNiV1.0。實驗採用的研究方法是以電弧熔煉法(arc-melting)將純元素熔配成塊材。再切成試片以進行微結構、電化學極化實驗及測試機械性質。以觀察不同V含量對合金性質的影響。本實驗以恆電流/恆電位儀測量此三種合金分別在四種溫度30oC、40oC、50oC、60oC下，以四種不同溶液分別為1M之除氧H2SO4、HNO3、HCl、NaCl溶液腐蝕之極化曲線測試，得以測得其腐蝕電位、腐蝕電流、鈍態區間電位，再相互比較。論文中會以SEM及XRD進行微結構的分析，以硬度試驗機進行硬度的測試，再以恆電流/恆電位儀進行電化學極化曲線分析，以尋求具有機械性質及耐腐蝕性質最佳組成的合金。此外，實驗中配置的三種合金會與市售的304不鏽鋼的測試結果做比較，結果顯示CoCrFeNiV0.2、CoCrFeNiV0.5和CoCrFeNiV1.0的三種合金在各四種溶液中的性能都會優於304不鏽鋼。
This thesis mainly studied the effects of vanadium content on the microstructures and corrosion properties of CoCrFeNiVx high-entropy alloys. The composition of these three alloys are CoCrFeNiV0.2, CoCrFeNiV0.5 and CoCrFeNiV1.0. The alloys were prepared by arc-melting. The specimens were then cut from the as-cast bulks and tested their microstructures, crystal structures, hardness and electrochemical polarization properties to observe the effects of V content on the corrosion properties of the alloys. In this experiment, the polarization tests of the three alloys were determined by a potentiostat/galvanostat at four temperatures of 30o, 40o, 50o, 60o; and the four solutions were 1M deoxidation H2SO4, HNO3, HCl and NaCl solutions. The microstructure analysis was carried out by SEM and XRD. The hardness test was carried out by microhardness tester, and the electrochemical polarization curves were analyzed by constant current/potentiostat to measure their properties. In addition, the three alloys were compared with the results of commercially 304 stainless steel. The results showed that the three alloys of CoCrFeNiV0.2, CoCrFeNiV0.5 and CoCrFeNiV1.0 outperformed the commercial 304 stainless steel in these four solutions.
