The Paton Welding Journal, 2010, №03



2010 №03 (02)

2010 №03 (04)

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TPWJ, 2010, #3, 14-18 pages
 
STUDY OF RESIDUAL STRESS AND MECHANICAL PROPERTIES OF 2Cr13 STAINLESS STEEL STEAM TURBINE BLADES BY DIFFERENT LASER SURFACE MODIFICATIONS


Journal                    The Paton Welding Journal
Publisher                 International Association «Welding»
ISSN                       0957-798X (print)
Issue                       № 3, 2010 (March)
Pages                      14-18
 
 
Authors
JIANHUA YAO¹, LIANG WANG¹, QUNLI ZHANG¹, ZHIJUN CHEN¹ and V.S. KOVALENKO^2
1Zhejiang University of Technology, Zhejiang, China
²Laser Technology Research Institute of the NTUU «Kiev Polytechnic Institute», Kiev, Ukraine
 
 
Abstract
As the key part of steam turbine, the blades work under the impact of high-speed steam and water droplet. Water droplet erosion on the inlet edge area is considered as the common failure pattern. In this paper, three laser surface modification ways including quenching, remelting and alloying were used to avoid water droplet erosion on the 2Cr13 stainless steel turbine blades. Residual stress and mechanical properties of the three modification methods were compared respectively. The result shows that the surface microhardness of blades increases after laser surface modifications. The tensile strength of the material is improved and meanwhile both the elongation percentage and reduction in cross sectional area are decreased. The impact fractures were all brittle fractures. The laser hardening zone presents residual compressive stress, and the heat-affected zone presents small transverse tensile stress.
 
 
Keywords: laser surface modification, turbine blade, residual stress, mechanical properties
 
 
Received:                ??.??.??
Published:               28.03.10
 
 
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