The 3rd Sandia Fracture Challenge is here!

The third Sandia Fracture Challenge is here!We invite to you participate in this next installment of our collaborative, blind assessment of predictions of ductile fracture.For the third SFC, we wanted to challenge the computational mechanics community to predict ductile fracture in anadditively manufactured structure. Additive manufacturing is a rapidly growing fabrication process that poses many challenges for the engineering community. Many mechanics questions arise from a class of materials with generally more heterogeneity and variability than traditionally formed materials. In this Challenge, we were able to design a Challenge geometry that could not have been conventionally machined, with complex internal structures, in order to go beyond our previous Challenges that were based on extruded 2D features. We also wanted to take advantage of better experimental metrology; we use Digital Image Correlation to measure field displacements and strains and have developed quantities of interest based on those field measurements that computationalists will have to predict. Given the complexity of predicting failure in an additively manufactured part, we are providing more background information than in previous Challenges, including micro-CT data of the Challenge test samples, and are giving 6 months for the predictions.

The third Sandia Fracture Challenge (SFC) rests on two previous successful Challenges that assessed ductile fracture in structural alloys. Through these two previous Challenges, contributors from over 30 institutions have participated in the prediction of elastoplastic deformation and fracture in a unique, unfamiliar geometry, given limited material test data and time for the predictions. These two Challenges highlighted successes and areas for further research in the prediction capability, from geometric variability due to manufacturing and types of base material calibration data to modeling of boundary conditions and thermomechanical coupling considerations. Both of these Challenges resulted in broad dissemination of the assessments in symposia at the ASEM IMECE Congress in 2013 and 2015 and special issues of the International Journal of Fracture in 2014 and 2016. There are links below to those IJF publications.

If you would like to see the current Challenge information (Information packet, base material tests data, images, etc.),we have created a Google Drive account that you can access from the link below. The core information packet is a powerpoint file that is ~50 MB. The main body of data for the Challenge is 2.5 GB in the “Challenge Info - Main” folder, and the raw micro–CT data is 470 GB in the “Challenge Info – Raw Micro-CT” folder. The raw micro-CT data is currently being uploaded, and the upload should be complete by December 22nd. There will be 18 folders around 26.5GB each. Please wait to download the micro-CT data until the upload is complete. A link to DIC images of the base material tests and EBSD data will be provided in a subsequent correspondence.The predictions are due on June 15th, 2017 (6 months from the issuance). Please email your predictions toSharlotte Kramer atslkrame@sandia.gov, and copy Brad Boyce atblboyce@sandia.gov.The results will be emailed to participants on July 15th, 2017. Also,please pass this invitation along to any other computational mechanicians who may be interested in participating.

Hyperlink to the SCF3 Information:https://drive.google.com/drive/folders/0B8nFwdOwWu0YQUJqNjc0WGF1STQ?usp=sharing

Hyperlink to the First SFC Lead Article:http://link.springer.com/article/10.1007/s10704-013-9904-6

Hyperlink to the First SFC Special Issue:http://link.springer.com/journal/10704/186/1/page/1

Hyperlink to the Second SFC Lead Article:http://link.springer.com/article/10.1007/s10704-016-0089-7

Hyperlink to the Second SFC Special Issue:http://link.springer.com/journal/10704/198/1/page/1

Regards,

Sharlotte Kramer

~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~

Sharlotte L.B. Kramer, Ph.D.

Sandia National Laboratories

Structural Mechanics Laboratory

505-284-9809 (office)

505-844-1924 (lab)

slkrame@sandia.gov

~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~