本研究係使用Thermo-calc熱力學模擬軟體設計六款以抗鹼性溶液腐蝕與抗高溫腐蝕為目標的含鉻鎳基合金並以真空電弧熔煉製作成試片。新合金可歸納為兩大類：高鉻含量合與低鉻含量合金。透過四種不同的腐蝕實驗，包括：極化實驗、氫氧化鈉浸沒實驗、鹽類浸沒實驗以及鹽類披覆實驗，新合金於不同環境中的抗腐蝕性質得以被評估，且實驗結果已完成與Monel-400與Ni-205進行比較。
實驗結果證實，鉻的添加有助於提升合金抗腐蝕性。在氫氧化鈉溶液中，鉻原子會誘發合金的二次鈍化，並且延緩過鈍化的發生。相較於高鉻合金，低鉻合金能夠避免在氫氧化鈉溶液中與鈉產生可溶性的化合物，展現良好的表面穩定性。另外，在高溫形成的保護性氧化鉻層則能夠阻止合金進一步被氧化。鉻含量超過10 wt.%的合金能在高溫腐蝕的環境下形成連續之氧化鉻，有效達到抗腐蝕效果。綜合各項腐蝕實驗結果顯示，在不同環境中，合金D2(Ni-20Cr)皆能夠展現卓越的抗腐蝕性質。

Six Cr-containing Ni-base alloys have been developed for the purpose to resist the attack of concentrated NaOH and molten salts. The content of the alloys was designed with the assistance of Thermo-Calc simulation software, and practically fabricated by vacuum arc melting (VAM). The newly designed alloys can be categorized as high Cr content alloys (alloy A, B and C) and low Cr content alloys (alloy D1, D2 and E). These newly designed alloys have been comprehensively evaluated with respect to their corrosion resistance under different conditions. Corrosion experiments were conducted, including polarization test, NaOH immersion test, salt immersion test and salt coated test. Experimental results have been compared to those of Monel-400 and Ni-205.
Research results illustrate the Cr addition does enhance the corrosion resistance of these alloys. The Cr atoms are able to induce a secondary passivation state and retard the beginning of the transpassivation in NaOH solutions. Furthermore, low Cr content alloys performed better in NaOH immersion test because the ability to avoid the formation of soluble compounds. In hot corrosion tests, the formation of protective Cr2O3 layer at elevated temperature can hinder further oxidation. Therefore, alloys with Cr more than 10wt.% can form continuous Cr2O3 layers effectively and result in better surface stability. To sum up, alloy D2 (Ni-10Cr) presented an outstanding corrosion resistance throughout all the corrosion tests.

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