Metallurgical Investigation into Ancient Iron Wares

Abstract

After having carried out the “Metallurgical Investigation into Ancient Iron Nails” (Tetsuto-Hagané 48 (1962), No. 1, pp. 44-49), the authors have made metallurgical investigation successively into the ancient iron wares such as clamps, rivets, ornamental fittings used in “Hôôdo” (main hall) of “Byôdô-in” temple, three-storied pagoda of “Meitsûji” temple and five-storied pagoda of “Daigo-ji” temple. Results obtained are summarized as follows.
(1) Manufacturing process,
Chemical compositions, nonmetallic inclusions and hardness are almost the same as those of the ancient nails, excepting two or three specimens made in a later period which have shown high P content.
(2) As to the cast iron product, the C content is somewhat higher and the P is somewhat less than cast iron used at present. The Si, Mn and S are noticeably low.
(3) Correlation of the quality of specimens and the age of their manufacture could not be grasped clearly, because there were a considerable dispersion of data between specimens manufactured in the same age. Nevertheless it seemed reliable that the older the manufactured age, the higher the purity is.