| 摘要 |
PURPOSE:To produce the grid for a lead storage battery with an excellent capability of recovering after it is left unattended following its excessive electric discharge by increasing the density of tin only at the interface between the grid and an active material. CONSTITUTION:A lead-tin-calcium alloy 1 (Sn contents: 0.7wt%, Ca contents: 0.05wt%) heat-melted at about 420 deg.C is poured into the space between a rotary drum 3 and a steel belt 4 through a gate 2. Here, a belt-shaped lead-tin alloy film 6 (Sn contents: 6wt%) is supplied so as to touch the melted alloy surface 5. Since the film is melted by heat from the melted alloy surface 5, and a alloy layer with a high tin density is formed on the surface. As the rotary drum 3 and the steel belt 4 are chilled with ice, the lead alloy passing through them is chilled and solidified into a slab 7, which is repeatedly rolled through a roller 9 and finally turned into a lead sheet 10 with the thickness of 1.0mm. Further more, this lead sheet 10 is expand-processed by means of an expander 11 into a grid 12. |
