摘要 |
A method for making a cylinder head cast from an aluminum alloy intended for use in internal combustion engines, and more particularly, a method for improving a portion of the cylinder head by a local heat treatment, comprises casting a cylinder head body from an aluminum alloy, directing a high density energy, such as TIG arc, laser, plasma arc or electron beam, to the surface of at least one region of the cylinder head body where a high strength is required, thereby rapidly remelting a surface layer in that region, and subsequently removing the irradiating energy and allowing the molten aluminum alloy of the surface layer to be rapidly cooled and solidified through heat transfer therefrom to the underlying matrix thereby forming a remelted, solidified layer. |