PURPOSE: To obtain a metal combined with crystalline fibers having superior heat resistance by melt-bonding and joining the mutual contact points of ceramic fibers to each other with frit in a preform and filling Al, an Al alloy, Mg or an Mg alloy into the voids in the resulting preform.

CONSTITUTION: A preform consisting of 4.5W35wt% frit, 8W10wt% org. binder and the balance heat resistance crystalline fibers is heat treated to vanish the binder by burning and to melt-bond and join the mutual contact points of the fibers to each other with the frit, so a preform having 75W95% void volume is obtd. Al, an Al alloy, Mg, or an Mg alloy is melted and filled into he pre form.