User Guideline

How to effectively uptake methodologies of fracture toughness evaluation in sheet metals

The user guideline developed under the framework of the ToughSteel project provides information about the fracture toughness evaluation of thin high-strength metal sheets to understand crack-related problems and the property implication on sheet metal formability and crashworthiness. The document summarises relevant findings obtained in previous RFCS projects and academic research, including PhD theses, post-doctorate works and scientific publications.

This guideline, contributing to a more efficient fracture resistance and crashworthiness prediction in different industrial applications, wishes to serve the industrial community as a reference document guiding users towards the characterisation of fracture toughness in thin metallic specimens with new cost-and-time-efficient methodologies for widespread implementation of fracture toughness measurements.

Definition of what is fracture toughness and how can be used in engineering materials design, its most-relevant parameters, and a compilation of standard testing procedures.

 The main experimental methodologies to characterise the plane stress fracture toughness of thin ductile metal sheets are described and analysed in terms of complexity, accuracy and quickness Special focus is put on the Essential Work of Fracture (EWF) methodology.

The user guideline includes recommendations about the most suitable testing methodologies, specimen geometry, specimen preparation method, etc. that can be applied during the different stages of advanced high-strength steels (AHSS) manufacturing, from the microstructural design to the implementation in cold-formed components.

Presentation of successful industrial case studies where fracture toughness measurements have been used to solve cracking related issues in cold-formed components to better exemplify the benefits of implementing a fracture mechanics approach in the design and implementation of AHSS sheets.

Get the guideline for applying fracture toughness in your processes and understand crack-related problems in high-strength metal sheets.

CEN Workshop Agreement

A novel and cost-efficient procedure to prepare sheet metal specimens for fracture toughness characterisation is described and a recent CEN Workshop Agreement (CWA) – CWA 17793: Test method for determination of the essential work of fracture of thin ductile metallic sheets – to characterise the essential work of fracture of metal sheets.