| 摘要 |
PROBLEM TO BE SOLVED: To stably produce a tin a plate having large tin grain size without strictly controlling the conditions in cooling after tin melting by controlling the surface roughness of a tin original plate by the regulation of peak side PPI. SOLUTION: A cold rolled steel plate obtd. by subjecting a steel stock to hot rolling, pickling and cold rolling is subjected to continuous annealing and is subjected to skinpass rolling by two stands using on lubricating oil to produce a tin original plate. At this time, in the skinpass rolling, the total draft is regulated to <=3%, by a work roll in the preceding step in which the average roughness by a surface roughness gauge is regulated to <=1.6μm, rolling reduction is executed at a draft of >=60% of the above total draft, and by a work roll in the trailing stand in which the average roughness is regulated to <=0.4μm, rolling reduction is executed at a draft of <=40% of the above total draft. Then, the tin original plate in which, at the time of showing the surface roughness by peak side PPI which is the number of peaks per inch measured by a peak count system, the peak side PPI in the case standard level from the average line of the extracted curves in regulated to 0.500μm in the positive direction is regulated to <=25000 can be obtd.
|
