• Bahrami, A.; Pech-Canul, M.I.; Soltani, N.; Gutiérrez, C.A.; Kamm, P.H.; Gurlo, A.: Tailoring microstructure and properties of bilayer-graded Al/B4C/MgAl2O4 composites by single-stage pressureless infiltration. Journal of Alloys and Compounds 694 (2017), p. 408-418

10.1016/j.jallcom.2016.09.284

Abstract:
The quantitative effect of the following parameters on the one single step pressureless infiltration characteristics of bilayer (B4C)p/rice-husk ash (RHA) porous preforms by aluminum alloys was investigated using the Taguchi method and analysis of variance (ANOVA): infiltration temperature and time, B4C particle size, RHA percentage, preform porosity and alloy magnesium content. Contribution determinations of each of the parameters on the bending strength of the resulting bilayer composites indicated that the parameter with the most significant effect is process temperature, with a contribution percentage of 79%. Verification tests conducted using the established optimum parameters show good agreement with those of projected values. A detailed examination of microstructure and potential chemical reactions, aided by thermodynamic analysis, allowed establishing conditions for suppressing or diminishing the impact of the deleterious Al4C3 phase.