Manufacturing Process for Thin Walled Casting of Intricate Shapes

本提案的目标是探索一种通过使用预热到铸造金属的金属熔化温度的永久模具制造复杂薄壁铸件的工艺的可行性和技术优点。模具将是一个冲床和一个模具的形式。熔融金属将被引入预热模具，然后预热冲头将降低到模具。将模具预热到熔化金属的温度将确保冲床和模具之间复杂的薄壁腔的完全填充。铸造金属的凝固是通过向冲床的冷却通道中注入预定数量的水或冷空气来实现的，这种数量的水或冷空气在下一次铸造时不需要对冲床和模具进行广泛的再加热。冲模材料为压铸工业中使用的合金钢。在型腔表面涂上一层合适的涂层，以方便铸件从模具中取出。本方案将采用铝合金作为铸造金属；然而，这种技术也可以应用于锡、铅、锌、镁和铜的合金。本工作将探讨最小铸件厚度、微观结构、强度和延展性以及循环时间。采用所提出的工艺，有可能获得比压铸工艺更小的壁厚，即0.040英寸或更小，而不需要在压铸工艺中使用压力。铸造金属的性能也可以得到提高。

The goal of this proposal is to explore the feasibility and technical merits of a process for making intricate thin wall castings by using permanent molds preheated to the metal melting temperature of the cast metal. The molds would be in the form of a punch and a die. The molten metal would be introduce into the preheated die and then the preheated punch would be lowered into the die. The preheat of the molds to the temperature of the molten metal would ensure complete filling of the intricate thin walled cavity between the punch and die. Solidification of the cast metal is achieved by introduction of a predetermined quantity of water or cold air into the cooling channel of the punch in such quantity that no extensive reheating of the punch and die is needed for the next casting. The punch and die material would be alloy steel as used in the die casting industry. A suitable coating would be employed on the cavity surfaces to facilitate extraction of the casting from the die. Aluminum alloy will be employed as the cast metal in this proposal; however, application of this techniques should also be possible to alloys of tin, lead, zinc, magnesium and copper. This work will explore the minimum casting thickness, the microstructure, strength and ductility properties, and the cycle time. With the proposed process it may be possible to attain wall thicknesses smaller than with the die casting process, i.e. 0.040" or less, without the need for pressure as is employed in the die casting process. Properties of the cast metal may also be enhanced.