Resource efficient hydrogen resistent high strength steel

Purpose and goal

The aim of the project was to increase the use of high-strength steels for weight and cost savings and reduced climate impact. The objectives set have largely been met, and two value chains with material manufacturer-component manufacturers and exposure of an end-user have been implemented. In parallel, fracture mechanical testing, metallography, chemical analysis and life cycle analysis have been successfully carried out in aim to support the work in the value chains. The project results has been summarized in 11 reports and two open seminars.

Expected results and effects

High-strength steel microstructures have been characterized for properties affecting the hydrogen sensitivity, so-called hydrogen traps. A literature study on their modeling has been conducted. Quantitative analyzes of the hydrogen content of the studied materials have been done as well as residual stress measurements with linked FEA. Environmental impact on fracture mechanic properties has been shown via the developed test method, which is supported by FEA. The participating companies have access to a collection of tools for assessing the hydrogen sensitivity in materials.

Planned approach and implementation

The project identified three main areas for knowledge improvement: quantitative and qualitative analysis of residual stresses, microstructure studies and hydrogen analysis and fracture mechanic testing. Microstructural studies have been done to show which features affect the sensitivity of hydrogen. The project has done practical and analytical analyzes of residual stresses in the materials. A fracture mechanic method to evalute of the environmental impact on the fracture probability has been developed and demonstrated for a wide range of materials with different properties