Improvement on Envirnment Degadation Resistence of Fe-18Al,Fe-18Al-5Cr Alloys by Surface Modification Treatment

• Main Authors: Cheng, Chich-Lung, 張傑榮
• Other Authors: Lee Pee-Yew
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/54392708657205141953

碩士 === 國立海洋大學 === 材料工程研究所 === 85 === Fe-18Al,Fe-18Al-5Cr經不同表面改質處理(鍍鎳,鍍鉻,裝匣處理等)對室 溫延性之影響結果如下: (1)電鍍鎳之後再施以攝氏300度退火1小時可增 加鐵鋁合金之延伸率,但效果並不顯著. (2)無電鍍鎳及無電鍍鎳經攝氏400度熱處理1小時之鍍層無法改善鐵鋁合 金之延伸率. (3)電鍍鉻因鍍層存在裂縫無法形成良好保護膜,對鐵鋁合金 之延性無幫助且有反效果. (4)裝匣處 理試片在攝氏700度處理者表面生成物為氧化鐵,此層從實驗結果看來對增 加試片延伸率無幫助;在攝氏900及1000度處理者表面以生成氧化鋁為主, 從實驗結果看是能發揮阻隔效用,增加試 片之延伸率,但氧化層太厚則會使提昇效果降低.(5)經裝匣處理雖可提昇 延伸率,但因此法是在高溫下進行長時間熱處理,會使基材晶粒變大,使拉 伸強度降低.(6)裝匣處理對Fe-18Al合金 延伸率提昇較有幫助,在攝氏900及1000度處理皆使延伸率大為提昇,其中 以在1000度處理8小時者有最佳之延伸率為19.6百分比,對Fe-18Al-5Cr之 研究結果須在1000度處理才有明顯效果, 最好的也是在1000度處理8小時,有14.2百分比的延伸率. The influence of surface modification treatments including surface plating Ni and Cr,and packing treatment to improve the room-temperature ductility of the Fe-18Al,Fe-18Al-5Cr alloya was investigated. The results were summarized below: (1) Annealing at 300 C for 1 hour after surface plating Ni can slightly increase the ductility at room-temperature of Fe-18Al alloy specimen. (2) Electroless plating Ni cannot improve specimens ductility. (3) The specimens which were treated by surface plating Cr cannot improve the ductility. (4) Fe2O3 forms at the specimen surface after packing treatment at 700 C.However, Al2O3 forms after treating at 900 C and 1000 C. Assording to the tensile test results,forming Al2O3 can improve specimens ductility. (5) Alough the specimens treated by packing have high elongation,it' s tensile strength decrease. (6) By packing treatment at 1000 C for 8 hours,Fe-18Al alloy specimen has highest elongation(19.6 percentages)and Fe-18Al-5Cr alloy specimen has highest elongation(14.2 percentages)