Corrosion behavior of Ni-Cr-Fe base superalloy GH984G in the sytnhetic coal ash and flue gas environment
The corrosion behavior and mechanism of a new Ni-Cr-Fe base superalloy GH984G was studied at 700℃in the synthetic coal ash and flue gas environments.The results indicated that a protective Cr2O3-rich scale formed on the samplc surface.During corrosion test the corrosion scale would spall slightly, which resulted in corrosion pits formed on the sample surface.Because Cr content of this superailoy is relatively high, GH984 alloy exhibited good corrosion resistance under the test conditions.The corrosion kinetics could be generally divided into two stages.At the initial corrosion stage, the corrosion rate was slow.The combination of oxidation and sulfidation reaction occurred and the protective Cr2O3-rich scale formed on the sample surfacc.However, the following corrosion stage was rapid mass loss, which showed corrosion pro ducts spalled from substrate.At this stage, the presence of the molten NiSO4 and Fe2(SO4)3 in local region led to corrosion pits.S-rich corrosion layer formed at the interface of corrosion layer and substrate, which resulted corrosion products spalled from substrate.
Ni-Fe-Cr base superalloy GH984G Coal ash corrosion Corrosion mechanism Ultra-supercritical
Guang-ming Liu Huachun Yang Qin Liang XiaochunYang Shanping Ren Jianhang Huang
School of Materials Science and Engineering, Nanchang Hangkong University, Nanchang 330063,China Dongfang Boiler Group Co.,Ltd,Material Research Institute, Zigong 643001, China
国际会议
长沙
英文
223-226
2016-10-16（万方平台首次上网日期，不代表论文的发表时间）