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Effect of carbon addition on microstructure and properties of boroncontaining steel sintered under different atmospheres |
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| รหัสดีโอไอ | |
| Creator | Nattaya TOSANGTHUM |
| Title | Effect of carbon addition on microstructure and properties of boroncontaining steel sintered under different atmospheres |
| Contributor | Wantana KOETNIYOM, Pisamorn CHANTAWET, Monnapas MORAKOTJINDA, Thanyaporn YOTKAEW, Pongsak WILA, Ruangdaj TONGSRI |
| Publisher | Metallurgy and Materials Science Research Institute, Chulalongkorn University |
| Publication Year | 2562 |
| Journal Title | Journal of Metals, Materials and Minerals |
| Journal Vol. | 29 |
| Journal No. | 1 |
| Page no. | 22-30 |
| Keyword | Liquid-phase sintering, Sintering atmosphere, Deboronization, Sintered steels |
| URL Website | http://ojs.materialsconnex.com/index.php/jmmm/index |
| Website title | Journal of Metals, Materials and Minerals |
| ISSN | 08576149;26300508 |
| Abstract | High performance sintered steels can be obtained by simultaneous tailoringmicrostructural feature and improving sintered density. Although sintered hardeningis used to produce sintered components with microstructural features providing hightensile strength and hardness, but the performance is limited by low ductility due tothe presence of porosity. Near full density can be achieved by liquid phase formingas a result of boron addition to a sintered steel. A liquid formed due to the eutecticreaction of Fe + Fe2B, spreads to interparticle spaces leading to densificationimprovement. Carbon is an indispensable element for high strength sintered steels.It plays important roles in both matrix microstructural development and intergranularliquid phase formation. This work has investigated the sintered Fe-1.5Mo-0.22B-xCsteels (x = 0.1 - 0.4 wt.%) sintered under hydrogen and vacuum atmospheres. It wasfound that the hydrogen-sintered Fe-1.5Mo-0.22B-xC steels hardly showedevidences of intergranular liquid phase whereas all experimental vacuum-sinteredsteels showed intergranular boride. Deboronization is believed to contribute to theintergranular boride absence in the hydrogen-sintered steels. However, when thehardening effect was taken into account, the strengthening by intergranular liquidphase in the sintered steels was less important than precipitation strengthening.Advantage of ductility was only obtained in the vacuum-sintered steels with Ccontents 0.1 wt.%, whose microstructures contained discontinuous boridenetworks along polygonal ferrite grain boundaries. In contrast, the presence ofcontinuous and thick boride networks caused embrittlement to the sintered steels. |
