Mesh resolution consideration for the viability prediction of lost salt cores in the high pressure die casting process

B. Fuchs and C. KörnerPublished Online:February 10, 2014pp 24-30

Abstract

High pressure die casting is limited in its geometry since a lost core technology as with sand or low pressure casting is not state-of-the art. Using lost cores made from sodium chloride may be a solution for high pressure die casting. Due to the high dynamical forces during the casting process, core failure is still a problem, especially for high ingate velocities. In this contribution the possibilities of numerical simulation are investigated to predict core failure during the casting process. Numerical results are created with different mesh resolutions and compared to evaluate the simulation results with according mechanical characterisation. In this way an objective approach to find process parameters based on the mechanical properties of the salt cores without costly and time consuming trial-and-error-testing could be established. Furthermore, a critical mesh resolution could be determined.

고압 다이캐스팅 공정에서 손실된 염심의 생존 가능성 예측을 위한 메쉬 해상도 고려

Keywords

고압 다이캐스팅은 모래나 저압 주조와 같이 핵심 기술을 상실한 기술이 최신 기술이 아니기 때문에 기하학적 구조가 제한적입니다. 염화나트륨으로 만든 로스트 코어를 사용하면 고압 다이캐스팅 솔루션이 될 수 있습니다. 주조 공정 중 높은 역학적 힘으로 인해 코어 파손은 특히 높은 인게이트 속도에서 여전히 문제입니다. 이 기여에서 수치 시뮬레이션의 가능성은 주조 공정 중 코어 파손을 예측하기 위해 조사됩니다. 수치적 결과는 다른 메쉬 해상도로 생성되고 기계적 특성에 따라 시뮬레이션 결과를 평가하기 위해 비교됩니다. 이러한 방식으로 비용이 많이 들고 시간이 많이 소요되는 시행착오 테스트 없이 염심 코어의 기계적 특성을 기반으로 공정 매개변수를 찾는 객관적인 접근 방식이 확립될 수 있습니다.

high pressure die casting, HPDC, lost core, salt core, undercuts in HPDC, hollow parts in HPDC, casting simulation, fluid-structure-interaction, FSI, finite difference method, FDM

키워드

고압 다이캐스팅 , HPDC , 로스트 코어 , 솔트코어, HPDC 의 언더컷 , HPDC 의 중공 부품 , 주조 시뮬레이션 , 유체 구조 상호 작용 , FSI , 유한 차분법 , FDM

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