| 摘要 |
PURPOSE:To easily manufacture a cylinder head at a low cost while the effect of prevention of cracks is sustained, by forming a fine graphite cast iron layer between valves and between the valves and a chambers. CONSTITUTION:In a roughly formed material of a cylinder head for a Diesel- engine, which is cast by a sand-mold process with the use of a molten material which is obtained by adding cerium as a deoxidizing agent in usual cast iron, inter valve sections between intake valves and exhaust valves and, and inter valve-chamber sections between the intake and exhaust valves and a chamber are subjected to a remelting and chilling process with the use of a TIG torch 8, and as a result, a remelted and chilled layer 9 is formed. Then, a high frequency heating coil 11 is disposed in the vicinity of the outer surface of the inter valve section, etc., to heat the latter before cooling. As a result, a fine graphite cast iron layer 12 which is the base material of the remelted and chilled layer 9 turned into ferrite, is obtained. Then, the cylinder head material is machine for finishing, thereby it is possible to obtain a cylinder head as a final product. |
