2015 年 87 巻 2 号 p. 109-116
The effects of pin-fins added to plate-shaped aluminum castings on their solidification characteristics were numerically examined by heat transfer and solidification simulation, and concepts for the casting designs of aluminum heat sink were also investigated. In the end effects E/T (E : end-effective range, T : baseplate thickness) of plate-castings with added pin-fins, there were differences depending on the casting and mold materials or pin-adding conditions. These findings suggested that the solidification characteristics of the castings are estimable and comparable using the end effects. Meanwhile there was a tendency for conditions with greater end effects to require longer solidification time. There were cases where liquid isolation occurred in pin-fins when solidification time was extremely long. It is considered that the conditions with these solidification processes may be unsuitable for manufacturing process using castings. In addition, it was suggested that the plot of heat-exchanging performance versus the end effects in aluminum heat sink may be useful for casting design, and many conditions have the potential to provide greater end effects by increasing the initial mold temperature.