Failure predictions in warm forming of 7075-T6 aluminum structural parts

International Deep Drawing Research Group 37th Annual Conference

Feister, T.^1 ; Kim, H.^2 ; Gwinn, A.^3 ; Schiller, T.^3 ; Austin, M.^4

KTH Parts Industries Inc., 8205 Business Way, Plain City

OH

43064, United States^1

EWI Forming Center, 1250 Arthur E Adams Drive, Columbus

OH

43221, United States^2

Tower International, 17672 North Laurel Park Drive, Livonia

MI

48152, United States^3

American Tooling Center, Inc., 4111 Mt. Hope Road, Grass Lake

MI

49240, United States^4

关键词: Accurate prediction;    Elevated temperature;    Failure prediction;    Forming limit curve;    Forming limit diagrams;    Fracture criteria;    Structural parts;    Weight reduction;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/418/1/012024/pdf
DOI  :  10.1088/1757-899X/418/1/012024

来源: IOP

【 摘 要 】

Today's automotive industry is increasingly adopting aluminum alloys. The main benefit of aluminum is a higher ratio of strength density compared to common steel alloys. Replacing steel with aluminum can give a weight reduction without loss of frame rigidity or crash safety. However, stamping aluminum is more difficult than steel because of its limited formability and the lack of experience with aluminum alloys for design and manufacturing requirements. Warm forming aluminum can help improve formability. Finite element analysis is a useful tool for predicting stamping failures. With accurate predictions stamping countermeasures can be made before tooling is cut and production has begun. Simulation was used to predict splits in a sidebar part formed at room and elevated temperatures. Forming limit curves were developed and used to test the formability using forming limit diagrams. Both forming limit diagrams and thinning were insufficient to predict the splits seen in the parts. This led to the use of additional fracture criteria that were successful in predicting the severity and locations of the splits.