The cooling system is a critical element in tooling for hot stamping high-strength aluminium alloys, for which very high quenching rates are required to ensure a supersaturated solid solution state in formed parts. To enhance cooling, ducts within the tools should be close and conformal to the surface die profile. Currently, ducts with curved profiles are made by drilling short straight lengths in die segments which are clamped together to form a complete die, which is expensive and hard to achieve the shape of duct with best cooling performance. To address these disadvantages, a novel method which enables efficient manufacture of conformal cooling systems by embedding a network of tubular cooling ducts within a cast matrix is presented in this paper. The feasibility of the proposed method of making ducts in the hot stamping die is demonstrated. Both experimental and computer-based die quenching tests using heated aluminium test pieces were undertaken to determine the cooling performance of a laboratory-scale tool set with cooling ducts. Simulations using the validated FE model were performed to investigate the effects of cross-sectional geometry, material and duct layout, on the quenching performance of the tools. It was found that ducts made of mild steel perform sufficiently well to make the use of high conductivity copper unnecessary. For a flat die surface, square section ducts provided highest cooling rates in comparison with circular and diagonal ones. The uniformity of die temperature increases with the decreased distance between neighbouring ducts, which indicates that a minimal gap is recommended without deteriorating tool strength. The developed tooling technology has the potential to provide a low-cost, highly efficient method of making conformal cooling ducts because the hot stamping die of high-strength aluminium alloy panels requires larger dimension, greater complexity and higher quenching rates.

冷却系统是用于热冲压高强度铝合金的模具中的关键元素，为此，需要非常高的淬火速度以确保成型零件中的过饱和固溶体状态。为了增强冷却效果，工具内的导管应靠近模具表面并与之相适应。当前，具有弯曲轮廓的风道是通过在模具段中钻短的直段来制造的，这些模具段被夹紧在一起以形成完整的模具，这是昂贵的并且难以获得具有最佳冷却性能的风道形状。为了解决这些缺点，本文提出了一种新颖的方法，该方法通过将管状冷却管网络嵌入浇铸基质中而能够有效地制造保形冷却系统。证明了所提出的在热冲压模具中制造管道的方法的可行性。使用加热的铝试件进行了基于实验和基于计算机的模具淬火测试，以确定带有冷却管的实验室规模工具套件的冷却性能。使用经过验证的有限元模型进行仿真，以研究横截面几何形状，材料和管道布局对工具淬火性能的影响。已经发现，由低碳钢制成的导管性能良好，从而无需使用高导电率的铜。对于平坦的模具表面，与圆形和对角风管相比，方形风管可提供最高的冷却速度。模具温度的均匀性随相邻导管之间距离的减小而增加，这表明建议在不降低工具强度的情况下最小间隙。