The pores grew in diameter and depth during the hydrolysis of
the CNTs/Al composite due to severe dissolution of the Al
matrix. Fig. 4c) shows that after 10 min of hydrolysis, the pores
grew to have diameters in the range of 50e100 mm Fig. 4d)
shows that after 20 min, almost all of the Al matrix had
corroded away after the hydrolysis; however, CNT clusters
remained in the composite because they were stable in the