Ductile Fracture Modeling of High-Strength Galvanized Steels at Borçelik with Altair

• Analytics & Modeling - Machine Learning
• Robots - Autonomous Guided Vehicles (AGV)

• Automotive
• Metals

• Product Research & Development

• Time Sensitive Networking
• Vehicle Performance Monitoring

• Testing & Certification

Borçelik, a leading galvanized steel producer in Turkey, was faced with the challenge of reducing emissions and fuel consumption in the automotive industry. This required the development of advanced materials and production processes. Fuel efficiency in vehicles largely depends on the successful design of the vehicle body structure and the development of technologies that can reduce its weight. However, while reducing the weight of the vehicle structure, it was crucial to maintain passenger safety. The main focus of this study was to investigate the ductile fracture behavior of the high-strength galvanized flat steel that forms the vehicle body structure.

Borçelik is a leading galvanized steel producer in Turkey, established in the early 1990s. The company operates as a partnership of Borusan Holding and ArcelorMittal, one of the world’s leading integrated steel and mining companies. Borçelik is engaged in manufacturing hot dip galvanized steel, cold-rolled steel, and hot-rolled (pickled and oiled) steel groups, all of which are industrial raw material inputs. The company offers a wide range of products, meeting manufacturer needs in industries like household appliances, automotive (OEM and Tier 1/2), panel radiators, construction, color coating, pipe and profile, packaging, metal goods, and steel service centers. Borçelik has a total production capacity of 1.5 million tons under the Borçelik brand and a metal processing capacity of 500 thousand tons under the Kerim Çelik brand.

Borçelik utilized Altair® Radioss™ to perform in-depth simulations and fatigue analyses of designs. This software capitalizes on machine learning and optimization techniques. With this structural analysis software, users can predict part behavior under various loads. The data derived from experimental tests can be applied to numerical calculations using different fracture models relating variables like stress triaxiality, lode angle, or equivalent plastic strain to material fracture. The /FAIL/BIQUAD failure model was particularly useful as it provided fast and accurate results. Users could create a fracture locus for materials with data from material libraries using only tensile test results. A Hosford-Coulomb ductile material fracture could be modeled with the /FAIL/EMC failure criterion, which supports 3D elements, especially for detailed fracture modeling. The Johnson-Cook fracture criterion, widely used in the industry, could be used in numerical calculations using the /FAIL/JOHNSON failure card. The /FAIL/FLD failure model could be employed to define the forming limit diagram (FLD), which represents the formability of the material, especially in sheet metal forming analysis.

• The use of Altair® Radioss™ allowed Borçelik to perform in-depth simulations and fatigue analyses of designs, leading to the development of advanced materials and production processes. The software's machine learning and optimization techniques enabled the prediction of part behavior under various loads. This led to a more efficient design of vehicle body structures, contributing to reduced emissions and fuel consumption in the automotive industry. The use of different fracture models also allowed for a more detailed understanding of the ductile fracture behavior of high-strength galvanized flat steel. This not only improved the quality of the products but also led to significant cost savings.

• Reduced the simulation time by nearly 50% using mass scaling
• Saved nearly 10% of scrap material
• Reduced costs by 5% after working with the design of experiments and applying numerical calculations through Altair simulation solutions