In the comparative example , {HEAD ~ the Pb alloy crystals} in {TAIL ~ the surface layer} have irregular forms with their crystal faces oriented at random, as in the base layer 18 in the example of the present invention 
in
In the comparative example , { HEAD ~ the Pb alloy crystals } in { TAIL ~ the surface layer } have irregular forms with their crystal faces oriented at random , as in the base layer 18 in the example of the present invention
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH