| 摘要 |
PURPOSE:To improve durability and heat collecting efficiency in the heat collecting fin of a solar heat collector, by forming a bluish, highly heat-resistant selective absorption film on the fin by plating cobalt on the surface of a metallic base material, and by treating it in an oxidizing atmospheric furnace. CONSTITUTION:A bluish, highly heat-resistant selective absorption film is formed on a cylindrical or a plate type heat collecting fin made of steel or copper, by plating cobalt on the fin and by putting it into a heat-treating furnace into which steam is fed from an overheated steam generator 10, and by keeping it in the furnace at 350-400 deg.C for 30min-2hr. With such an arrangement, a heat collecting fin, of which durability and heat colecting efficiency are improved, can be obtained. |
