摘要
基于激光选区熔化(SLM)技术制造的随形冷却模具,凭借其优异的冷却性能,能够显著提高加工效率,有效降低生产成本,成为未来注塑成型模具的重要发展方向,但目前在使用SLM技术成形随形冷却模具内部的圆形流道方面仍存在诸多挑战。在SLM成形时,随形冷却模具内部圆形流道的结构主要表现为悬垂圆孔结构,若直接使用传统工艺策略成形悬垂圆孔结构易出现翘曲、粘粉等缺陷,同时由于随形冷却模具内部流道复杂的特点,其内部流道无法通过添加支撑辅助成形。采用在模具外侧添加支撑结构的方法,可调整模具成形角度,增强悬垂圆孔结构自支撑性,但会增加额外成形时间与成形材料,导致生产成本增高。优化悬垂圆孔结构无支撑成形工艺,实现在不添加支撑结构的前提下满足随形冷却模具对流道成形质量要求,能够有效降低随形冷却模具生产成本并获得高质量成型件。本文对金属悬垂圆孔结构成形工艺策略进行优化,以316L不锈钢悬垂圆孔结构为对象,分析了工艺策略、孔径对悬垂圆孔成形质量的影响。采用一种基于加工层角度自适应的下表面工艺区域划分策略,研究该工艺区策略对于无支撑金属悬垂圆孔成形的适用性,并使用该工艺制造冷却模具样件,对成件的成形质量进行分析。结果表明采用基于加工层角度自适应的下表面工艺区域划分策略可明显抑制成形过程中的翘曲行为。使用该工艺策略成形的随形水冷模具样件无明显质量缺陷,内部流道的表面质量与成形精度满足使用要求。
Conformal cooling molds manufactured via laser selective melting(SLM)technology can significantly improve processing efficiency and effectively reduce production costs because of their excellent cooling performance,making it an important development direction for future injection molding molds.However,there are still many challenges in using SLM technology to form circular flow channels inside conformal cooling molds.During SLM,the structure of the circular flow channel inside the conformal cooling mold mainly presents as an overhanging circular hole structure.Defects such as warping and powder sticking are likely to occur if the overhanging circular hole structure is formed directly via the traditional processing strategy.Moreover,owing to the complex characteristics of the internal flow channel,it cannot be formed by adding support assistance.By adding a support structure on the outside of the mold,the forming angle of the mold can be adjusted to enhance the self-supporting ability of the overhanging circular hole structure,but this increases the additional forming time and material,resulting in increased production costs.Optimizing the non-supporting forming process of the overhanging circular hole structure to meet the quality requirements of the conformal cooling mold for runner forming without adding support structures can effectively reduce the production cost of the conformal cooling mold and obtain high-quality molded parts.In this study,the forming process strategy for metal overhanging circular hole structures was optimized.Taking the 316L stainless steel overhanging circular hole structure as the object,the influences of the process strategy and hole diameter on the forming quality of overhanging circular holes were analysed.A bottom surface process area division strategy based on the adaptive angle of the processing layer was adopted to study its applicability for the formation of unsupported metal overhanging circular holes.The process was then used to manufacture a cooling mold sample,and the formi
作者
王迪
李浩然
胡伟南
牛吉梅
刘林青
马迎
WANG Di;LI Haoran;HU Weinan;NIU Jimei;LIU Linqing;MA Ying(School of Mechanical and Automotive Engineering,South China University of Technology,Guangzhou 510641,China;Guangzhou City University of Technology,Guangzhou 510800,China)
出处
《铸造技术》
CAS
2024年第8期752-762,共11页
Foundry Technology
基金
国家自然科学基金(52475349)。
关键词
激光选区熔化
悬垂圆孔结构成形
无支撑成形
工艺优化
成形质量
随形水冷模具
selective laser melting
overhanging round hole structure forming
unsupported forming
process optimization
forming quality
conformal water-cooled molds
