Influence of boron contents on microstructure, mechanical properties and shielding effect of Fe–W–C alloy

• Published in: Journal of alloys and compounds Vol. 803; pp. 466 - 475
• Main Authors: Dewen, Tang, Shuliang, Zou, Liang, Yan
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 30.09.2019; Elsevier BV
• Subjects: B content; Boron; Brittle fracture; Density; Fe-W-C-B alloy; Ferrous alloys; Gamma rays; Hardness; Iron alloys; Mechanical properties; Microstructure; Radiation shielding; Shielding performance; Surface hardness; Transmittance; Tungsten; Vacuum sintering; Mechanical properties; B content; Microstructure; Shielding performance; Fe-W-C-B alloy
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2019.06.061

By using vacuum sintering method, the shielding materials made of iron-tungsten-carbon-boron (Fe–W–C–B) alloys with different boron (B) contents were prepared. The influences of different B contents on mechanical properties, shielding performance and microstructures of the alloys were investigated. The research results showed that with increasing B content, the fracture of alloys changed from plastic to brittle fractures and the higher the B content was, the more serious the brittle fracture. Moreover, the content of brittle amorphous phase FeWB increased and therefore the hardness and density of alloys increased at first and then reduced. When the B content was 2.5%, the alloy phase was mainly composed of Fe2B, Fe3(C, B) and α-Fe phases, with compact microstructure, shown as continuous network microstructure and tiny, long, round rod-like microstructure. In this case, the density, tensile strength and hardness of alloys were 10.05 g/cm3, 410 MPa and 468 HV, respectively. The γ-ray shielding performance of the alloy reduced at first, then increased and finally declined with the increase of B contents. When the B content was 1.5%, the half-value thickness reached to the minimum (about 6.36 mm). The transmittance of neutron shields reduced at first and then increased in a low-energy zone (0–4 MeV). When the B content was 2.5%, the alloys showed the lowest transmittance about 0.10842. •Good shielding effect and mechanical properties of Fe-W-C-B series alloy is prepared through liquid phase sintering.•Fe–W–C–B series alloy are mainly composed of Fe2B, Fe7W6, Fe3(C, B) and matrix phase a-Fe.•When the B content is increased to 2.5%, the microstructure shows continuous network and alloys have the best mechanical properties.•Prepared Fe–W–C–B series alloys are significantly superior to lead in shielding γ ray. When the B content was 1.5%, there was the minimum half-value thickness of about 6.36 mm.•The transmittance of the neutron shield reduced at first and then increased in a low-energy zone (0–4 MeV). When the B content was 2.5%, the alloys showed the lowest transmittance of about 0.10842.