Materials corrosion in molten LiF-NaF-KF salt
Materials corrosion in molten LiF-NaF-KF salt
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DOI：
10.1016/j.jfluchem.2008.05.008
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发表时间：
2009-01-01
影响因子：
1.9
通讯作者：
Allen, Todd R.
中科院分区：
文献类型：
--
作者：
Olson, Luke C.;Ambrosek, James W.;Allen, Todd R.
对高温合金Hastelloy-N、Hastelloy-X、Haynes-230、Inconel-617和Incoly-800H在熔融氟化物FLiNaK(LiF-NaF-KF：46.5-11.5-42mol%)中进行了腐蚀试验，目的是了解腐蚀机理，并对这些合金在熔融氟化物盐热交换器和储热应用中的适用性进行排名。这些试验是在850摄氏度的密封石墨坩埚中，在氩气覆盖下进行500小时的。腐蚀的主要原因是合金中铬的脱合金化，这种影响在这些合金的晶界上尤为明显。腐蚀引起的重量损失一般与合金的初始铬含量相关，并与腐蚀试验后测得的盐中铬含量一致。对Ni-201和Nb-1Zr两种无铬合金也进行了试验。Ni-201是一种添加少量合金化的近乎纯净的镍合金，具有良好的耐腐蚀性，而Nb-1Zr合金具有广泛的腐蚀侵蚀性。石墨坩埚可能通过促进测试坩埚壁上碳化物相的形成而加速了腐蚀过程，但并没有改变基本的腐蚀机理。(C)2008 Elsevier B.V.Elsevier B.V.保留所有权利。
Corrosion tests of high temperature alloys, Hastelloy-N, Hastelloy-X, Haynes-230, Inconel-617, and Incoloy-800H were performed in molten fluoride salt, FLiNaK (LiF-NaF-KF:46.5-11.5-42 mol%) with the goal of understanding the corrosion mechanisms and ranking these alloys for their suitability for molten fluoride salt heat exchanger and thermal storage applications. The tests were performed at 850 degrees C for 500 h in sealed graphite crucibles under an argon cover gas. Corrosion was noted to occur predominantly by dealloying of Cr from the alloys, an effect that was particularly pronounced at the grain boundaries of these alloys. Weight-loss due to corrosion generally correlated with the initial Cr-content of the alloys, and was consistent with the Cr-content measured in the salts after corrosion tests. Two Cr-free alloys, Ni-201 and Nb-1Zr, were also tested. Ni-201, a nearly pure Ni alloy with minor alloying additions, exhibited good resistance to corrosion, whereas Nb-1Zr alloy exhibited extensive corrosion attack. The graphite crucible may have accelerated the corrosion process by promoting the formation of carbide phases on the walls of the test crucibles, but did not alter the basic corrosion mechanism. (C) 2008 Elsevier B.V. Elsevier B.V. All rights reserved.