Characterization of TiAl based alloys with various content of carbon

4th International Conference Recent Trends in Structural Materials

Klimová, A.^1 ; Lapin, J.^1 ; Pelachová, T.^1

Institute of Materials and Machine Mechanics, Slovak Academy of Sciences, Dúbravská cesta 9, Bratislava 3

845 13, Slovakia^1

关键词: Coexisting phasis;    Effect of carbons;    Energy dispersive spectroscopies (EDS);    Lamellar matrixes;    Nominal composition;    TiAl-based alloys;    Vickers microhardness;    X-ray diffraction analyses (XRD);   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/179/1/012038/pdf
DOI  :  10.1088/1757-899X/179/1/012038

来源: IOP

【 摘 要 】

TiAl based alloys prepared by induction melting with nominal compositions Ti-(37.5-41)Al-(3.5-4)Nb-1Mo-0.1B-xC (at.%), where carbon content x is ranging from 3 to 7 at.%, were characterised by optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction analysis (XRD) and elemental LECO analysers of light elements (O, N and C). Morphology and volume fraction of coexisting phases are quantitatively analysed using computerised image analyser. The effect of carbon content on Vickers microhardness and hardness of the alloys is evaluated and discussed. The microstructure of the alloys consists of fine-grained lamellar matrix with elongated Ti2AlC particles dispersed in the whole volume of the ingots. The volume fraction of the carbide particles increases with the carbon content of the studied alloys from 8 to 18 vol.%. The average Vickers hardness of the ingots doesn't show the significant variations with their carbon content, but the hardness considerably exceeds the average values in the surface regions where the small rod shape particles are densely distributed in the matrix.