Browse > Article

Mechanical properties of $Al_2O_3/Mo/MnO_2$ composite  

Park, Hyun (Division of Advanced Materials & Chemical Engineering, Kangwon National University)
Kim, Kyung-Nam (Division of Advanced Materials & Chemical Engineering, Kangwon National University)
Publication Information
Journal of the Korean Crystal Growth and Crystal Technology / v.16, no.4, 2006 , pp. 172-179 More about this Journal
Abstract
When $Al_2O_3-MoO_3$ mixture is reduced, $MoO_3$ is only reduced to Mo at $900^{\circ}C$. But a compound between $Al_2O_3$ and Mo is not formed up to $1300^{\circ}C$. In the case of $Al_2O_3-MoO_3-MnO_2$ mixture, an intermediate compound $Mn_2Mo_3O_8$ is firstly formed at $900^{\circ}C$ and changes to $MnAl_2O_4$ at $1100^{\circ}C{\sim}1300^{\circ}C$. $Al_2O_3/Mo/MnO_2$ composite are manufactured by a selective reduction process in which Mo is only reduced in the powder mixture of $Al_2O_3,\;MoO_3\;and\;MnO_2$ oxide. For $Al_2O_3/Mo$ composite, the average grain size was not changed with increasing Mo content because of inhibition of grain growth of $Al_2O_3$ matrix in the presence of Mo particles. Fracture strength increased with increasing Mo content due to phenomenon of grain growth inhibition of $Al_2O_3$ matrix. Hardness decreased because of a lower hardness value of Mo, whereas fracture toughness increased. For $Al_2O_3,\;Mo\;and\;MnO_2$ composite, grain growth was facilitated by MnOB and it showed a lower fracture strength because of grain growth effect with increasing Mo and $MnO_2$ content. Hardness decreased because of the grain growth of matrix and coalesced Mo particles to be located in grain boundary, whereas fracture toughness increased.
Keywords
$Al_2O_3,\; Mo\; and\; MnO_2$ composite; Selective reduction process; Hot pressing;
Citations & Related Records
연도 인용수 순위
  • Reference
1 C.H. Kim and H.J. Kim, 'The study of alumina ceramic to metal bonding', J. Kor. Ceram. Soc. 15(2) (1978) 89
2 C.H. Kim and C.T. Kim, 'Bonding behavior of alumina ceramic to metals', J. Kor. Ceram. Soc. 16(3) (1979) 169
3 G.C. Wei and P.F. Becher, 'Development of SiC-whisker- reinforced ceramics', Am. Ceram. Soc. Bull. 64(2) (1985) 298
4 W.H. Taun and R.J. Brook, 'The toughening of alumina with nickel inclusions', J. Eur. Ceram. Soc. 6 (1990) 31   DOI   ScienceOn
5 C. Toy, M. Demirci, S. Onurlu, M. Sadik Tasor and T. Baykara, 'A colloidal method for manganese oxide addition to alumina powder and investigation of properties', J. Mater. Sci. 30(16) (1995) 4183   DOI   ScienceOn
6 W.H. Taun, H.M. Wu and R.Z. Chen, 'Effect of sintering atmosphere on the mechanical properties of Nil $AI_{2}O_{3}$ composite', J. Eur. Ceram. Soc. 17 (1997) 735   DOI   ScienceOn
7 R.R. Tummala, 'Ceramic and glass ceramics packaging in the 1990s', J. Am. Ceram. Soc. 74(5) (1991) 895   DOI
8 R. Lundberg, L. Kahlman, R. Pompe and R. Warren, 'SiC-whisker-reinforced $Si_{3}N_{4}$ composites', Am. Ceram. Soc. Bull. 66(2) (1987) 330
9 T. Sekino and K. Niihara, 'Fabrication and mechanical properties of fine-tungsten-dispersed alumina-based composites', J. Mater. Sci. 32 (1997) 3943   DOI   ScienceOn
10 M.G. Nicholas, Joning of Ceramics, Champman and Hall Press, London (1990)
11 W.H. Taun and Y.T. Chiu, 'Toughening alumina with metallic and zirconia inclusions', CSJ Series-Publicated of the Ceramic Society of Japan 2 (1999) 337
12 B.R. Lawn, A.G. Evans and D.B. Marshall, J. Am. Ceram. Soc. 63 (1980) 574   DOI   ScienceOn
13 M. Nawa, T. Sekino and K. Niihara, 'Fabrication and mechanical behaviour of $AI_{2}O_{3}/Mo$nanocomposites', J. Mater. Sci. 29 (1994) 3185   DOI   ScienceOn
14 K. Niwa, N. Kamehara, K. Yokouchi and Y Imanada, 'Multilayer ceramic circuit board with a copper conductor', Adv. Cream. Mater. 2(4) (1987) 832
15 M.I. Mendelson, 'Average grain size in policrystalline ceramics', J. Am. Ceram. Soc. 52(8) (1969) 443   DOI
16 C.O. Mchugh, T.J. Whalen and M. Humenik, Jr., 'Dispersion- strengthened aluminum oxide', J. Am. Ceram. Soc. 49(9) (1966) 486