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Indexed by:期刊论文

Date of Publication:2013-10-01

Journal:NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS

Included Journals:SCIE、EI、Scopus

Volume:312

Page Number:97-103

ISSN No.:0168-583X

Key Words:High current pulsed electron beam; Surface irradiation; FeCrAl coating; Microstructure; High temperature corrosion resistance

Abstract:The surface microstructure of arc-sprayed FeCrAl coating irradiated by high current pulsed electron beam (HCPEB) with long pulse duration of 200 mu s was characterized by using optical microscopy, scanning electron microscopy and X-ray diffractometry. The distribution of chemical composition in modified surface layer was measured with electron probe micro-analyzer. The high temperature corrosion resistance of FeCrAl coating was tested in a saturated Na2SO4 and K2SO4 solution at 650 degrees C. After HCPEB irradiation, the coarse surface of arc-sprayed coating was changed as discrete bulged nodules with smooth and compact appearance. When using low energy density of 20 J/cm(2), the surface modified layer was continuous entirely with an average melting depth of similar to 30 mu m. In the surface remelted layer, Fe and Cr elements gave a uniform distribution, while Al and O elements agglomerated particularly at the concave part between nodule structures to form alpha-Al2O3 phase. After high temperature corrosion tests, the FeCrAl coating treated with HCPEB of 20 J/cm(2) remained a glossy surface with weight increment of similar to 51 mg/cm(2), decreased by 20% as compared to the initial sample. With the increasing energy density of HCPEB irradiation, the integrity of surface modified layer got segmented due to the formation of larger bulged nodules and cracks at the concave parts. For the HCPEB irradiation of 40 J/cm(2), the high temperature corrosion resistance of FeCrAl coating was deteriorated drastically. (c) 2013 Elsevier B.V. All rights reserved.