Effect of two-stage sintering process on microstructure and mechanical properties of ODS tungsten heavy alloy

34Citations
Citations of this article
27Readers
Mendeley users who have this article in their library.
Get full text

Abstract

Oxide dispersion strengthened (ODS) tungsten heavy alloys have been considered as promising candidates for advanced kinetic energy penetrator due to their characteristic fracture mode compared to conventional tungsten heavy alloy. In order to obtain high relative density, the ODS tungsten heavy alloy needs to be sintered at higher temperature for longer time, however, induces growth of tungsten grains. Therefore, it is very difficult to obtain controlled microstructure of ODS tungsten heavy alloy having fine tungsten grains with full densification. In this study, two-stage sintering process, consisted of primary solid-state sintering and followed by secondary liquid phase sintering, was introduced for ODS tungsten heavy alloys. The mechanically alloyed 94W-4.56Ni-1.14Fe-0.3Y2O3 powders are solid-state sintered at 1300-1450 °C for 1 h in hydrogen atmosphere, and followed by liquid phase sintering temperature at 1465-1485 °C for 0-60 min. The microstructure of ODS tungsten heavy alloys showed high relative density above 97%, with contiguous tungsten grains after primary solid-state sintering. The microstructure of solid-state sintered ODS tungsten heavy alloy was changed into spherical tungsten grains embedded in W-Ni-Fe matrix during secondary liquid phase sintering. The two-stage sintered ODS tungsten heavy alloy from mechanically alloyed powders showed finer microstructure and higher mechanical properties than conventional liquid phase sintered alloy. The mechanical properties of ODS tungsten heavy alloys are dependent on the microstructural parameters such as tungsten grain size, matrix volume fraction and tungsten/tungsten contiguity, which can be controlled through the two-stage sintering process. © 2007 Elsevier B.V. All rights reserved.

Cite

CITATION STYLE

APA

Lee, K. H., Cha, S. I., Ryu, H. J., & Hong, S. H. (2007). Effect of two-stage sintering process on microstructure and mechanical properties of ODS tungsten heavy alloy. Materials Science and Engineering A, 458(1–2), 323–329. https://doi.org/10.1016/j.msea.2007.01.118

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free