Question

Estimate (a) the maximum, and (b) the minimum thermal conductivity values (in W/m-K) for a cermet that contains 85 vol% carbide particles in a metal matrix. Assume thermal conductivities of 20 and 66 W/m-K for the carbide and metal, respectively.

Answer 1

Answer:

Explanation:

k_max = 26.9 w/mk

  k_min  =  22.33 w/mk

Explanation:

a) the maximum thermal conductivity is given as

K_MAX = k_m v_m + k_p v_p

where k_m is thermal conductvitiy of metal

k_p is thermal conductvitiy of carbide

v_m = proportion of metal in the cement = 0.15

v_p = proportion of carbide in the cement = 0.85

$K_MAX = k_m v_m + k_p v_p$

            = 66*0.15 + 20*0.85

           k_max = 26.9 w/mk

b) the minimum thermal conductivity is given as

$k_min = \frac{ k_{carbide} *k_{metal}}{k_{metal} v_{carbide} +k_{carbide} v_{metal}}$

          = \frac{20*66}{20*0.15 +66*0.85}

        k_min  = 22.33 w/mk