The isothermal section of the Co-Mo-Zr ternary system at 1000 °C was investigated by using 29 alloys. The annealed alloys were examined by means of x-ray diffraction, optical microscopy, and electron probe microanalysis. It was confirmed that three ternary phases, λ1 (Co0.5-1.5Mo1.5-0.5Zr, hP12-MgZn2), ω (CoMoZr4) and κ (CoMo4Zr9, hP28-Hf9Mo4B), exist in the Co-Mo-Zr ternary system at 1000 °C. And the experimental results also indicated that there are sixteen three-phase regions at 1000 °C. Thirteen of them were well determined in the present work: (1) (γCo) + Co11Zr2 + Co23Zr6, (2) (γCo) + Co23Zr6 + ε-Co3Mo, (3) Co23Zr6 + ε-Co3Mo + μ-Co7Mo6, (4) (Mo) + μ-Co7Mo6 + Co2Zr, (5) (Mo) + Co2Zr + λ1, (6) (Mo) + Mo2Zr + λ1, (7) λ1 + Mo2Zr + CoZr, (8) Co2Zr + CoZr + λ1, (9) Mo2Zr + CoZr2 + ω, (10) κ + Mo2Zr + ω, (11) CoZr2 + liquid + ω, (12) (βZr) + liquid + ω and (13) (βZr) + κ + ω. The homogeneity of λ1 spans in the range of 28.66-50.77 at.% Co and 15.71-37.03 at.% Mo, and that for ω is within the range of 18.66-23.64 at.% Co and 8.53-14.68 at.% Mo. The homogeneity range for κ is from 8.09 at.% to 9.94 at.% Co and 23.13 at.% to 25.58 at.% Mo. The maximum solubility of Zr in μ-Co7Mo6 phase, Mo in Co2Zr phase and Co in Mo2Zr phase were determined to be 6.17, 11.27 and 9.14 at.%, respectively. While the solubility of Zr in ε-Co3Mo and (γCo) phases, Mo in Co11Zr2 and CoZr phases were detected to be extremely small. According to this work, the Co23Zr6 phase contained 15.61 at.% Mo and 12.7 at.% Zr. In addition, the maximum solubility of Co and Zr in (Mo) phase and Mo in (γCo) phase were measured to be 3.50, 5.44 and 7.40 at.%, respectively.
Co-Mo-Zr system electron probe microanalysis isothermal section x-ray diffraction
This is a preview of subscription content, log in to check access.
The financial supports from Ministry of Industry and Information Technology of China (Grant No. 2015ZX04005008) and Project of Innovation-driven Plan in Central South University (Grant No. 2015CX004) are greatly acknowledged.
D. Moskowitz and L.L. Terner, TiN Improves Properties of Titanium Carbonitride-Base Materials, Int. J. Refract Met. Hard Mater., 1986, 5, p 13-14Google Scholar
Ĵ. Zackrisson and H.-O. Andrén, Effect of Carbon Content on the Properties, Int. J. Refract Met. Hard Mater., 1999, 17(4), p 265-273CrossRefGoogle Scholar
P. Ettmayer, H. Kolaska, W. Lengauer, and K. Dreyer, Ti(C, N) Cermets-Metallurgy and Properties, Int. J. Refract Met. Hard Mater., 1995, 13(6), p 343-351CrossRefGoogle Scholar
S. Zhang, Titanium Carbonitride-Based Cermet: Processes and Properties, Mater. Sci. Eng. A, 1993, 163(1), p 141-148CrossRefGoogle Scholar
S. Ahn and S. Kang, Effect of Various Carbides on the Dissolution Behavior of Ti(C0.7N0.3) in a Ti(C0.7N0.3)-30Ni System, Int. J. Refract Met. Hard Mater., 2001, 19(4–6), p 539-545CrossRefGoogle Scholar
W.T. Kwon, J.S. Park, S.W. Kim, and S. Kang, Effect of WC and Group IV Carbides on the Cutting Performance of Ti(C, N) Cermet Tools, Int. J. Mach. Tools Manuf., 2004, 44(4), p 341-346CrossRefGoogle Scholar
L. Chen, W. Lengauer, and K. Dreyer, Advances in Modern-Containing Hardmetals and Cermets, Int. J. Refract Met. Hard Mater., 2000, 18(2–3), p 153-161CrossRefGoogle Scholar
X. Zhang, N. Liu, C. Rong, and J. Zhou, Microstructure and Mechanical Properties of TiC-TiN-Zr-WC-Ni-Co Cermets, Ceram. Int., 2009, 35(3), p 1187-1193CrossRefGoogle Scholar
X. Zhang and N. Liu, Effects of ZrC on Microstructure, Mechanical Properties and Thermal Shock Resistance of TiC-ZrC-Co-Ni Cermets, Mater. Sci. Eng. A, 2013, 561, p 270-276CrossRefGoogle Scholar
Y. Li, N. Liu, X. Zhang, and C. Rong, Effect of Mo Addition on the Microstructure and Mechanical Properties of Ultra-Fine Grade TiC-TiN-WC-Mo2C-Co Cermets, Int. J. Refract. Met. Hard Mater., 2008, 26(3), p 190-196CrossRefGoogle Scholar
M. Zhang, Q. Yang, W. Xiong, L. Zheng, B. Huang, S. Chen, and Z. Yao, Effect of Mo and C additions on magnetic properties of TiC–TiN–Ni cermets, J. Alloys Compd., 2015, 650(25), p 700-704CrossRefGoogle Scholar
A. Davydov and U.R. Kattner, Revised Thermodynamic Description for the Co-Mo System, J. Phase Equilib. Diffus., 2003, 24(3), p 209-211CrossRefGoogle Scholar
X.J. Liu, H.H. Zhang, C.P. Wang, and K. Ishida, Experimental Determination and Thermodynamic Assessment of the Phase Diagram in the Co-Zr System, J. Alloys Compd., 2009, 482(1-2), p 99-105CrossRefGoogle Scholar
A. Durga and K.C.H. Kumar, Thermodynamic Optimization of the Co-Zr System, Calphad, 2010, 34(2), p 200-205CrossRefGoogle Scholar
R.J. Pérez and B. Sundman, Thermodynamic Assessment of the Mo-Zr Binary Phase Diagram, Calphad, 2003, 27(3), p 253-262CrossRefGoogle Scholar
C.K. Bataleva, V.V. Burnasheva, V.V. Burnasheva, V.Ya. Markiv, G.N. Ronami, and S.M. Kurnetsova, Phase Diagram of the Cobalt-Zirconium System, Moscow Univ. Chem. Bull., 1970, 11(5), p 557-561Google Scholar
V.V. Pet’kov and M.Y. Teslyuk, Zirconium-Molybdenum-Cobalt System, Dopov. Akad. Nauk Ukr. RSR Ser. A, 1971, 23(2), p 182-185Google Scholar
P. Rogl, H. Nowotny, and F. Benesovsky, New κ-Borides and Related Phases (Filled Up Re3B-Phases), Monatsh. Chem., 1973, 104(1), p 182-193CrossRefGoogle Scholar
C. Lin, C. Zhang, S. Wang, P. Zhou, and Y. Du, Phase Equilibria of the Co-Mo-Zr Ternary System at 1100 °C, J. Phase Equilib. Diffus., 2017, 38(4), p 552-560CrossRefGoogle Scholar
S. Wang, C. Zhang, C. Lin, Y. Peng, and Y. Du, Measurement of 900 °C Isothermal Section in the Mo-Ni-Zr System, J. Phase Equilib. Diffus., 2016, 37(6), p 672-679CrossRefGoogle Scholar