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Title: Improved the microstructures and properties of M3:2 high-speed steel by spray forming and niobium alloying

Abstract

The microstructures and properties of spray formed (SF) high-speed steels (HSSs) with or without niobium (Nb) addition were studied. Particular emphasis was placed on the effect of Nb on the solidification microstructures, decomposition of M{sub 2}C carbides, thermal stability and mechanical properties. The results show that spray forming can refine the cell size of eutectic carbides due to the rapid cooling effect during atomization. With Nb addition, further refinement of the eutectic carbides and primary austenite grains are obtained. Moreover, the Nb addition can accelerate the decomposition of M{sub 2}C carbides and increase the thermal stability of high-speed steel, and also can improve the hardness and bending strength with slightly decrease the impact toughness. The high-speed steel made by spray forming and Nb alloying can give a better tool performance compared with powder metallurgy M3:2 and commercial AISI M2 high-speed steels. - Highlights: • Spray forming can effectively refine the microstructure of M3:2 steel. • Niobium accelerates the decomposition of M{sub 2}C carbides. • Niobium increases the hardness and bending strength of spray formed M3:2 steel. • Spray-formed niobium-containing M3:2 steel has the best tool performance.

Authors:
 [1];  [1]; ; ; ;  [1];  [2];  [1]
  1. State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Xueyuan Road 30, Haidian District, Beijing 100083 (China)
  2. State Key Laboratory of Non-Ferrous Metals and Process, General Research Institute for Non-Ferrous Metals, Beijing 100088 (China)
Publication Date:
OSTI Identifier:
22587160
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Characterization; Journal Volume: 117; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ATOMIZATION; AUSTENITE; BENDING; CARBIDES; COOLING; DECOMPOSITION; EUTECTICS; FLEXURAL STRENGTH; HARDNESS; MICROSTRUCTURE; NIOBIUM; PERFORMANCE; POWDER METALLURGY; POWDERS; SOLIDIFICATION; SPRAYS; STEELS

Citation Formats

Lu, L., Hou, L.G., E-mail: lghou@skl.ustb.edu.cn, Zhang, J.X., Wang, H.B., Cui, H., Huang, J.F., Zhang, Y.A., and Zhang, J.S.. Improved the microstructures and properties of M3:2 high-speed steel by spray forming and niobium alloying. United States: N. p., 2016. Web. doi:10.1016/J.MATCHAR.2016.04.010.
Lu, L., Hou, L.G., E-mail: lghou@skl.ustb.edu.cn, Zhang, J.X., Wang, H.B., Cui, H., Huang, J.F., Zhang, Y.A., & Zhang, J.S.. Improved the microstructures and properties of M3:2 high-speed steel by spray forming and niobium alloying. United States. doi:10.1016/J.MATCHAR.2016.04.010.
Lu, L., Hou, L.G., E-mail: lghou@skl.ustb.edu.cn, Zhang, J.X., Wang, H.B., Cui, H., Huang, J.F., Zhang, Y.A., and Zhang, J.S.. Fri . "Improved the microstructures and properties of M3:2 high-speed steel by spray forming and niobium alloying". United States. doi:10.1016/J.MATCHAR.2016.04.010.
@article{osti_22587160,
title = {Improved the microstructures and properties of M3:2 high-speed steel by spray forming and niobium alloying},
author = {Lu, L. and Hou, L.G., E-mail: lghou@skl.ustb.edu.cn and Zhang, J.X. and Wang, H.B. and Cui, H. and Huang, J.F. and Zhang, Y.A. and Zhang, J.S.},
abstractNote = {The microstructures and properties of spray formed (SF) high-speed steels (HSSs) with or without niobium (Nb) addition were studied. Particular emphasis was placed on the effect of Nb on the solidification microstructures, decomposition of M{sub 2}C carbides, thermal stability and mechanical properties. The results show that spray forming can refine the cell size of eutectic carbides due to the rapid cooling effect during atomization. With Nb addition, further refinement of the eutectic carbides and primary austenite grains are obtained. Moreover, the Nb addition can accelerate the decomposition of M{sub 2}C carbides and increase the thermal stability of high-speed steel, and also can improve the hardness and bending strength with slightly decrease the impact toughness. The high-speed steel made by spray forming and Nb alloying can give a better tool performance compared with powder metallurgy M3:2 and commercial AISI M2 high-speed steels. - Highlights: • Spray forming can effectively refine the microstructure of M3:2 steel. • Niobium accelerates the decomposition of M{sub 2}C carbides. • Niobium increases the hardness and bending strength of spray formed M3:2 steel. • Spray-formed niobium-containing M3:2 steel has the best tool performance.},
doi = {10.1016/J.MATCHAR.2016.04.010},
journal = {Materials Characterization},
number = ,
volume = 117,
place = {United States},
year = {Fri Jul 15 00:00:00 EDT 2016},
month = {Fri Jul 15 00:00:00 EDT 2016}
}
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