三种700℃级超超临界燃煤锅炉备选高温合金煤灰腐蚀行为（可编辑）.docVIP

三种700℃级超超临界燃煤锅炉备选高温合金煤灰腐蚀行为 三种 700℃级超超临界燃煤锅炉备选高温合金煤灰腐蚀行为 鲁金涛，谷月峰，杨珍 西安热工研究院有限公司，西安，710032 ； 摘要:研究了三种 700℃超超临界燃煤锅炉备选高温合金Inconel 740，CCA 617，GH 2984 在 760℃现役机组煤灰腐蚀介质中的高温腐蚀行为。结果表明：Ni 基合金 Inconel 740 和 CCA 617 均能形成保护性的 Cr2O3 氧化膜，局部点蚀为其主要失效形式。点蚀区域氧化膜为多层 结构，由外到内依次为 Ni Co O 、Cr O TiO、Al O 以及少量内层硫化物；较高 Cr、Al 含 2 3 2 3 量提高了 Inconel 740 的耐蚀性能；挥发性产物与氧化膜微区溶解降低了CCA 617 合金氧化 膜的致密性。GH 2984 因含有较多的Fe 未能形成保护性的氧化膜，氧化膜分层生长，且出 现了严重的剥落现象。 关键词：700℃超超临界；高温合金；煤灰腐蚀；腐蚀机理 Coal Ash Induced Corrosion of Three Candidate Materials for Superheater Boiler Tubes of Advanced Ultra-supercritical Power Station LU Jintao, GU Yuefeng, YANG Zhen Xi′an Thermal Power Research Insititute Co., Ltd., Xi′an, 710032 ABSTRACT: Coal ash induced corrosion of three alloys, i.e. Incone1740，CCA617 and GH2984 was studied at 760°C which are candidate materials of superheater boiler tubes for the proposed 700℃ level advanced ultra-supercritical power station. The results indicated that a protective Cr O scale formed on Ni-based alloys of Inconel 740 and CCA 617 ，while a small amount of 2 3 corrosion pits with multi-layer oxides which consisted of Ni Co O, Cr O TiO??、Al O [did the 2 3 2 3 authors identify the oxides? By what means?] and minor sulfide were observed. The relatively high Cr, Al content may be responsible to the corrosion resistance of Inconel 740. Volatile products and oxide film dissolution in micro area, however, reduced the density of the oxide scale formed on CCA 617. Non-protective oxide scale formed on GH 2984 due to its high Fe content, while the scale was layered with serious inner sulfide and spall