工業用純Al板における二三の現象(V)高温加工の影響（補遺）

抄録

Some phenomena about the hot-rolled plate were investigated by microhardness tests and microscopic examinations. The results obtained are as follows: (1) The reduction of hot-rolling of about 77% had to be given in order to change the cast structure to the wrought structure, in which recrystallized grains were found. In a lighter reduction, both the working and the thermal influences ununiformly affect the inner parts of hot-rolled stock. (2) A comparatively homogeneous structure was obtained by a severer reduction than that, but when the total reduction is too large, the stock becomes again heterogeneous with the fall of temperature. (3) Larger partial reduction of hot-rolling gives superior properties to cold-rolled sheets and it was found that the size of the grains in the surface layer may become coarser or finer than that in the inner layers according to the hot-rolling conditions.