Porous metal matrix hydride (PMH) compacts of LaNi5 with aluminium as the matrixmaterial were prepared in the whole range 0Al<1 where VAl is the volume fraction of the aluminium matrix of the composite. The thermal conductivity, keffvs. VAl was determined. For the interpretation of the results, an equation was developed for a composite material consisting of two phases and porosity. The equation consists of two terms and has only one fitting parameter B1, which is related to the quality and quantity of the interfacial contact surfaces. A second parameter B2 is calculated from the limiting conditions. A calculated curve fits well the experimental results in the whole range 0Al<1. In the practically important range ≈0.15Al<0.5 (0.075Al<0.3), where fAl is the weight fraction of aluminium, the thermal conductivity keff of the PMH compacts lies in the range 8–23 W m−1 K−1 and exceeds by orders of magnitude the keff value of powder hydride beds of LaNi5 (less than 0.5 W m−1 K−1).
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