朱荣华

摘 要：轻量化铝活塞结构复杂，铸造模具由多个组件构成，轻量化铝活塞在铸造过程中存在脱模拉毛、局部变形、模具磨损快，铝活塞铸造内表面分模面粗糙，飞边严重，铸造精度不理想等问题。针对轻量化铝活塞难以做到精密铸造的问题，深入研究铸造工艺与模具结构关系，多次铸造实验和探索，改进内模通水、轨道加工工艺，改变外模滑块、销孔模组件结构。获得了一种能大幅度提升轻量化铝活塞铸造精度的模具组件改进技术。关键词：铝活塞;轻量化;模具组件;精密铸造;技术改进中图分类号：TG233  文献标识码：A  文章编号：1671-7988（2020）11-172-06

Abstract： The structure of lightweight aluminum piston is complex， and the casting mold is composed of many components. During the casting process of lightweight aluminum piston， there are many problems， such as demoulding and roughening， local deformation， rapid wear of mold， rough parting surface of internal surface of aluminum piston casting， serious flash， and unsatisfactory casting accuracy. Aiming at the problem that it is difficult to achieve precision casting of lightweight alumi -num piston， the relationship between casting process and mold structure was studied in depth. Many casting experiments and explorations were carried out to improve the water flow and track processing technology of internal mold and change the structure of slide block and pin hole module of external mold. An improved die assembly technology which can greatly improve the casting precision of lightweight aluminum piston was obtained.Keywords： Aluminum piston; Lightweight; Mold component; Precision Casting; Technical improvementCLC NO.： TG233  Document Code： A  Article ID： 1671-7988（2020）11-172-06

引言

活塞轻量化，是当前国际上较主流的一种活塞设计取向，随着各国对汽车排放要求的不断提高，节能减排是主流。活塞轻量化结构是为了满足现代高速高负荷，低排放发动机。其实质是在一定的高度、外径、形状的前提下，通过对活塞的结构优化来达到，即能减轻重量，又不降低机械强度。轻量化活塞常采用凹陷设计，造成活塞铸造模具结构复杂，铸造精度难以解决。各活塞生产厂家都期待获得一种简单高效，可实现精密铸造的模具组件。本改进的目的在于克服上述现有技術中的不足之处，提供一种简单、稳定、高效的，可实现轻量化活塞精密铸造量产的模具组件改进技术。

1 结构特点

轻量化铝活塞系指销孔座外侧靠近顶部方向带有三个轴向凹坑的铝活塞。活塞呈柱形，顶部实，中下部内收带空腔。……