Key Issues for Quality Stabilization of Aluminum （铝的质量稳定的关键问题）.pdf

Key Issues for Quality Stabilization of Aluminum Die Casting Y. Furukawa Toyota Motor Corporation, Toyota, Japan Y. Tsunekawa Toyota Technological Institute, Nagoya, Japan Copyright 2013 American Foundry Society ABSTRACT degrades its mechanical property. In addition, it has a large impact on fluidity. As a result, it is reported that With aluminum diecasting method, molten metal rapidly this could cause the variation in product quality.1, 2, 3 The forms solidification structure, and creates a boundary molten metal infused in cavities becomes solid as soon as between a layer called chill layer, which consists of fine it touches a mold and its surface forms a chill layer. The crystals, and internal structure. While the chill layer chill layer is known to have a better mechanical property contributes to the assurance of airtightness, it has a latent than that of internal structure.4 On the other hand, it problem that it would become an origin of peering at became more evident that there is a problem of separation mold release or an initiating site of chipping during at a boundary between a chill layer and internal structure process. These days due to the progress in net-shape during machining. Moreover, in a heat-insulated casting technology, which is contributing to the reduction condition which does not create chill layers or when of machining cost, there are more cases that near-surface castings are removed from a mold while it is still at