Open AccessMECHANICAL PROPERTIES OF FORGED TUNGSTEN HEAVY ALLOYS
Author(s) -
Ondřej Kovářík,
Jaroslav Čech,
Jiří Čapek,
Michal Hajíček,
Jakub Klečka,
J. Siegl
Publication year - 2020
Publication title -
acta polytechnica ctu proceedings
Language(s) - English
Resource type - Journals
ISSN - 2336-5382
DOI - 10.14311/app.2020.27.0149
Subject(s) - materials science , forging , tungsten , residual stress , composite material , toughness , alloy , anisotropy , composite number , elastic modulus , modulus , fracture toughness , metallurgy , physics , quantum mechanics
Tungsten heavy alloys are composite materials containing spherical tungsten particles embedded in binder matrix. Their excellent mechanical properties can be further improved by rotary forging. This paper aims to gain deeper understanding of the forging process by investigating the local elastic modulus, hardness, and residual stress of individual phases in W6Ni3Co pseudo-alloy. The resulting global properties of the composite material such as stress-strain behavior, fracture toughness and fatigue crack growth rate behavior are also studied. The results show that sintered and quenched material consists of highly textured matrix containing nearly perfect single crystal spheres of pure W. The rotary forging leads to significant lattice deformations destroying the texture and significantly increasing the hardness of both WNiCo matrix and W particles and making residual stresses in W particles anisotropic with increased compression along the longitudinal axis of the forged part.