Issue 1/June 2017

ASSOCIATIONS / UNIVERSITIES / B2B 协会/大学/B2B

DIECASTING-DIALOGUE.COM

SIMULATION AND APPLICATION OF CASTING PROCESS FOR ALUMINIUM-AUTOMOBILE PISTON 铝合金汽车活塞铸造工艺的模拟及应用 The piston is one of the most important parts in the engine. It is worked in the hard condition with high temperature, high load, high speed, poor lubrication and cooling, etc. By means of comparison actual casting trial and simulation, the foundry process can be analyzed well in order to get the reasonable solution for the piston casting defect. The study showed that the piston skirt porosity on casting caused by the different casting wall thickness in partial area, which generated the hotspot. The additional riser is hard to be applied for solidification in order effectively caused by the casting tool space constraints.

活塞是汽车发动机的重要零件之一，活塞工作条件相当严 酷，如高温、高负荷、高速运动、润滑不良和冷却困难等。 利用实际试制浇铸及模拟分析软件相结合的方法，分析铸件 的成形过程，得到解决活塞铸造缺陷的方案。研究表明，活 塞铸件裙部区域形成缩孔的原因是铸件局部壁厚不均匀，从 而有热节产生。受模具结构限制难以通过辅助冒口实现铸件 有效补缩和顺序凝固。

In this study, the cooling design on the mold is optimized by simulation in order to eliminate the porosity of the castings, which also is verified the feasibility by the actual production. The casting mass: 398g; the casting volume: 172mm3; the dead head volume: 27.4mm3; the casting system volume: 45mm3; the part boundary dimension: Φ88. The requirements on mechanical properties borne for the piston casting under the engine operating condition: the max. load power is 155kW (211PS)/5500rpm, the max. load torque is 350Nm/1200-4000rpm, and the material hardness shall not be lower than HB140.

本研究针对活塞铸件，提出通过模拟分析手段优化模 具冷却设计，从而达到消除铸件缩孔缺陷的方法，并 通过实际生产验证其可行性。铸件质量：398 g；铸件 体积：172mm3；冒口体积：27.4mm3；浇铸系统体 积：45mm3；零件外形尺寸约为：Φ88。该活塞铸件 在发动机工况下所城守的机械性能要求：最大功率承载 功率为155kW（211PS）/5500rpm，最大承载扭矩为 350Nm/1200-4000rpm；材料硬度不得低于HB140。

改进前后的宏观检验缺陷图

Macrographic Examination Defect Graph Before and After Improvement

3D Structural Drawing of the Piston Casting

Foundry Planet Magazine

活塞铸件三维结构图

a) S hrinkage Cavity On the Casting Side Before Improvement a) 改进前进浇有缩孔

b) N  o Shrinkage Cavity On the Casting Side After Improvement b）改进后进浇侧无缩孔

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