Integration of advanced experiments, computation and data for Duplex Stainless Steel joining innovation

Project Information

i-Weld

Grant agreement ID: 823786

DOI

10.3030/823786

Project closed

EC signature date 26 October 2018

Start date 1 May 2019

End date 28 February 2025

Funded under

• EXCELLENT SCIENCE - Marie Skłodowska-Curie Actions

Total cost

€ 506 000,00

EU contribution

€ 473 800,00

Coordinated by

LIVERPOOL JOHN MOORES UNIVERSITY
United Kingdom

Periodic Reporting for period 2 - i-Weld (Integration of advanced experiments, computation and data for Duplex Stainless Steel joininginnovation)

Reporting period: 2023-03-01 to 2025-02-28

Summary of the context and overall objectives of the project

Welding and joining of advanced alloys such as Stainless steels (SS) and related systems are one of the most important R&I areas directly relevant to economies, health, and environments. Advanced grade Duplex stainless steel (DSS) with a mixed ferrite-austenite (+) structure, has superior mechanical and corrosion resistance with increased applications in many industries. The complex alloying system naturally results in complicated microstructural zones, phases and properties, which are difficult to control and predict during welding, joining and related processes due to the thermal-mechanical-physical processes. The issues become more challenging for situations such as multi-pass welding, hybrid structures and dissimilar materials. This is a critical issue affecting the development of data-led R&I, wider applications and management of the materials as well as the development of more efficient manufacturing/production processes.
The overall objective of the project is to develop systematic collaborative advanced research on the key controlling structures, phases and properties with integrated experiments and modelling. This will enhance the combined functional performances, applications, materials design and manufacturing techniques. It will contribute to the current global effort in knowledge based digital manufacturing by tackling the critical scientific issues. The scientific objectives have been achieved through 7 collaborative work packages following a dynamic mechanism. The main technical works in the project have been focused on developing an in-depth understanding and data of compositions, microstructure, phase ratio (e.g. ferrite/austenite, precipitations) of the fusion zones and heat affected zones; the key controlling factors and mechanisms of surface treatment and corrosion resistance; the development of CAE system with advanced data; establishing the effects of composition, defects and other parameters (e.g. temperature) on the fundamental physical and interface parameters through physical modelling; research on welding and joining of dissimilar/hybrid materials and data systems development.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

The work conducted has covered many different welding, joining, surface treatment and associated manufacturing. The work has established key in-depth knowledge of the structure and properties of different welding processes of DSSs and related manufacturing. The structure and composition in different welding processes of DSS are established in detail, including the critical conditions for the formation of inclusions, which is detrimental to the properties of the weldment. The project integrated mathematical modelling, engineering simulation and experimental data for predicting the microstructure with different thermal histories including the volume fraction of ferrite and austenite phases in the welding zones, critical cooling rate for some precipitation particles and residual stresses, all of which are important for controlling the structures and properties of the joint. The effect of key elements and surface conditions on the corrosion resistance and the operating mechanisms is established. Some key data was established including the critical pitting temperatures for duplex stainless steels, the effect of post-weld cleaning of duplex stainless steel, influences of surface roughness, key elements (Mn, O, N, etc.) in the DSSs and welding fillers. The in-depth knowledge is complimentary to conventional industrial available data and provides key data for establishing the critical corrosion limiting structural parameters.
The intersectoral collaboration has developed practical parametrised models and data. The work covers programming through python and developing advanced approaches for determining the materials properties for the welding zones. A method to study/predict the complex performance of complex structures and properties (combination of mechanical and thermal properties, anisotropy) has been established inducing the use of the ANN, which is important for enhancing the program application. The work dissimilar welding covered different combinations of materials including Lean DSS, Standard DSS, Super DSS, and Hyper DSS with other materials groups (single phase SS, different steels, nonferrous metals) with a wide range of new welding processes and data.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The scientific work has advanced the R&I capacity in DSS welding, as well as impact generations. The in-depth data and research have advanced the scientific understanding of phase (ferrite, austenite) structure formation, precipitation and critical conditions for corrosion resistance. The data system developed covered in-depth knowledge of the behaviours of secondary particles, intermetallic phases and mechanical-thermal-corrosion properties in similar and dissimilar materials systems of DSSs. The project effectively integrated engineering modelling, physical modelling, ANN and machine learning, which offers a powerful tool for DSS welding design, development for optimum conditions and synergy of key properties in different systems.
The i-weld have completed a total of 110 person-months of secondments, 9 of which were sponsored self-funding with TC partners. The project has published over 20 journal and conference papers, presented at over 12 conferences. The project has organised several focused industrial-academic workshops and led/participated in general conferences including major industrial conferences (e.g. Swedish Production Symposium 2024). The work was reported on social media and outreach activities reaching thousands of school children and college students as well as the general public. The collaborative work has resulted in 4 new collaborative projects with over 20 partners from Europe, Asia and Africa including 4 SMEs. The project also contributed to student enterprise and a new start up high-tech company in one of the partners (Sweden) specialised in the composition design of advanced alloys.
Work on the main scientific objectives has made contribution of the action to the improvement of the R&I potential within Europe and/or worldwide in DSS welding and joining with direct economic and environmental impacts. The work has made a clear impact on enhancing the potential and future career prospects of the staff members at different stages (Early career researchers (ECR), mid-stage researchers and senior researchers) as well as technical and management staff. The project has made an impact on industrial practice through close industrial-academic collaborations. The outreach activities include open days, engagement activities, training of SME and other activities promoting STEM in Young people and the general public. The partners also effectively collaborated on research and scholarly activities in education and industrial training impacting a wider community.
The intersectoral and/or international secondments and the networking activities implemented have enhanced the development and sustainability of new and lasting research collaborations. The R&D and networking activities have already established 5 new major collaborative EU projects worth millions of euros. Several new proposals and projects are currently being developed. The new proposals involve a diverse group of new partners building on the framework of i-weld, which will further enhance the development of each partner and the consortium.

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