抄録
Fundamental studies about the Preece test for the sprayed zinc coatings on iron were carried out in order to ascertain whether this test is adoptable in J. I. S. or not.
From the results of several experiments, it was concluded that the Preece can be adopted in J.I.S. as in the case of galvanized zinc coating with nearly the same manual. But in the case of sprayed zinc coating, the following points should be taken in mind.
i) The solution velocity of zinc which is nearly proportional to the concentration of CuSO4 in solution, is much greater than that of galvanized zinc.
ii) The cleaning of the coating by 2% H2SO4 solutions for 15 seconds before the test has no great effect on the dissolution of zinc. But as the removal of H2SO4 from the coating is rather difficult in the case of sprayed coating, it is preferable to omit this treatment.
