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论文类型：期刊论文

发表时间：2010-08-01

发表刊物：16th International Symposium on Metastable, Amorphous and Nanostructured Materials

收录刊物：SCIE、EI、CPCI-S、Scopus

卷号：504

期号：SUPPL. 1

页面范围：S508-S511

ISSN号：0925-8388

关键字：Low energy high current pulsed electron beam (LEHCPEB); Melting and heating modes; Craters; Deformed structures; Surface alloying; Surface hardening

摘要：High current pulsed electron beam is a recently developed technique for surface modification. The pulsed electron irradiation introduces concentrated energy depositions in the thin surface layer of the treated materials, giving rise to an extremely fast heating and subsequent rapid cooling of the surface together with the formation of dynamic stress waves. Improved surface properties (hardness, corrosion resistance) can be obtained under the "melting" mode when the top surface is melted and rapidly solidified (10(7) K/s). In steels, this is essentially the result of nanostructures formed from the highly undercooled melt, melt surface purification, strain hardening induced by the thermal stress waves as well as metastable phase selections in the rapidly solidified melted layers. The use of the "heating" mode is less conventional, combining effects of the heavy deformation and recrystallization/recovery mechanisms. A detailed analysis of a FeAl alloy demonstrates grain size refinement, hardening, solid-state enhanced diffusion and texture modification without modification of the surface geometry. (C) 2010 Elsevier B. V. All rights reserved.