The Role of the Atmosphere on Boron-Activated Sintering of Ferrous Powder Compacts
| Autor: | R. de Oro Calderon, Herbert Hutter, Vassilka Vassileva, Herbert Danninger, C. Gierl-Mayer, Susanne Strobl |
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| Rok vydání: | 2018 |
| Předmět: |
010302 applied physics
Materials science Metallurgy Metals and Alloys Sintering chemistry.chemical_element 02 engineering and technology 021001 nanoscience & nanotechnology 01 natural sciences Ferrous Atmosphere chemistry Mechanics of Materials 0103 physical sciences 0210 nano-technology Boron Embrittlement |
| Zdroj: | Powder Metallurgy Progress. 18:6-20 |
| ISSN: | 1339-4533 |
| DOI: | 10.1515/pmp-2018-0002 |
| Popis: | Boron has been known to activate densification during sintering of ferrous powder compacts, though with risk of embrittlement. In the present study, specimens Fe-B and Fe-C-B prepared from standard atomized iron powder with addition of ferroboron Fe-21%B were sintered in different atmospheres, and the resulting microstructures and properties were studied. It showed that the activating effect of boron is observed during sintering in argon and in hydrogen while sintering in N2containing atmospheres results in rapid deactivation of boron, through formation of stable BN. In hydrogen atmosphere, surface deboronizing was observed to considerable depth. Ar is chemically inert, but Ar trapped inside closed pores tends to inhibit further densification. The impact energy data indicated that the embrittling effect of boron is enhanced significantly by presence of carbon. In the fracture surfaces, transgranular cleavage fracture can be observed both at very low and high impact energy values. |
| Databáze: | OpenAIRE |
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