两种低偏析镍基高温合金抗热腐蚀性能的研究  

HOT CORROSION BEHAVIOR OF NICKEL-BASE SUPERALLOYS DZ68 AND K438G WITH LOW SEGREGATION

作　　者：于忠锋[1] 郑志[2] 刘恩泽[2] 于永泗[1] 朱耀宵[2] 

机构地区：[1]大连理工大学材料科学与工程学院,大连116023 [2]中国科学院金属研究所,沈阳110016

出　　处：《中国腐蚀与防护学报》2008年第5期277-281,共5页Journal of Chinese Society For Corrosion and Protection

摘　　要：研究了DZ68和K438G合金在900℃、75%Na2SO4+25%NaCl熔盐中的热腐蚀行为。结果表明,低偏析DZ68合金成分、组织均匀,腐蚀过程中发生均匀腐蚀;K438G合金成分不均匀,组织中存在共晶相,腐蚀过程中发生局部腐蚀。两种合金内腐蚀层腐蚀产物相同,外腐蚀层腐蚀产物不同。在本文试验的条件下,组织成分均匀的DZ68合金的抗热腐蚀性能略好于含Cr较高的K438G合金。Hot corrosion behavior of DZ68 directionally solidified nickel-base superalloy and K438G cast superalloy was studied in molten salt of 75% Na2SO4 ＋ 25% NaCI at 900 ℃. The results showed that the hot corrosion property of DZ68 alloy was better than that of K438G alloy since DZ68 alloy had a more homogeneous composition and mierostructure resulting from controlling segregation elements, though the chromium content of DZ68 alloy is lower than that of K438G alloy. Both alloys had different corrosion products in their outer corrosion layer.

关 键 词：热腐蚀 低偏析 定向凝固高温合金 

分 类 号：TG172.62[金属学及工艺—金属表面处理]