The European forging and casting industry faces the challenge of significantly reducing its energy consumption without compromising the quality of manufactured components. Conventional heat treatments, which are essential for achieving the required mechanical properties, account for a substantial share of energy consumption and process-related emissions. Furthermore, their dependence on fossil fuel-fired furnaces increases both costs and exposure to increasingly stringent regulatory requirements.
To address this challenge, the GREENLINE project consortium (Green Electrified Ultrafast In-Line Heat Treatment for Net-Zero Forging and Casting), coordinated by AZTERLAN, will develop and validate a new generation of in-line heat treatments for casting and forging components, aiming to reduce energy consumption associated with heat treatment by up to 40%, significantly cut CO₂ emissions, and shorten treatment times by up to 80%, while maintaining the metallurgical properties required by industry.
The proposal is based on an innovative concept built on AZTERLAN’s years of research into in-line heat treatments and waste heat recovery: making use of the heat retained by components after the casting or forging process, thereby avoiding the need to reheat them before heat treatment. To achieve this, GREENLINE will combine electric heating technologies with ultra-fast cooling systems capable of precisely controlling the material’s metallurgical transformations. The expected result is a significant reduction in energy consumption during heat treatment, together with improved efficiency and sustainability of industrial processes.
As explained by Dr Ana Fernández, researcher, project manager at AZTERLAN and coordinator of the GREENLINE project, “Heat treatments can account for up to 40% of a plant’s total energy consumption and between 20% and 30% of manufacturing costs.” Currently, heat treatments are usually carried out as a separate stage in the forging and/or casting process, requiring components to be reheated once casting or forming operations have been completed. This “inefficiency” considerably increases energy consumption, production times and associated emissions.
“It is important to understand that, in GREENLINE, the heat already present in the process ceases to be wasted and becomes an active process variable.” With this approach, “the project’s real technical challenge lies in accurately controlling thermal evolution and metallurgical transformations to ensure that the final component delivers exactly the performance required for its intended application.”
The technology developed by the research team will be validated under real production conditions at the facilities of CIE Legazpi (forging) and BETSAIDE (casting, within its ADI product range), demonstrating its industrial feasibility from metallurgical, energy, economic and environmental perspectives.
AZTERLAN: Developing efficient heat treatment strategies
In addition to coordinating the project, AZTERLAN will play a leading role in developing in-line heat treatment strategies and validating the metallurgical performance of the proposed solutions. The research team will focus primarily on defining thermal cycles, studying the microstructural evolution of materials, characterising the resulting mechanical properties, and assessing the energy, environmental and economic impact of the new technologies.
The coordination of GREENLINE builds upon several years of AZTERLAN research into in-line heat treatments and the use of residual heat as a process variable. This previous knowledge has resulted in proprietary methodologies, technological developments and several patented technologies related to energy optimisation and advanced control of metallurgical transformations.
These developments include:
- Development projects for in-line heat treatment of forged components (+ info).
- Methodologies for optimising efficient heat treatments (+ info).
- Production of austempered ductile iron through controlled cooling processes and residual heat utilisation (+ info) (patented technology).
GREENLINE therefore represents the continuation of a research line that AZTERLAN has been building for several years, offering the opportunity to integrate this knowledge into a European development initiative with a strong industrial focus and to advance towards more efficient, sustainable and competitive manufacturing processes.
More about GREENLINE
GREENLINE brings together 11 organisations from five European countries (Spain, Germany, Italy, Belgium and Poland) in a multidisciplinary consortium comprising industrial manufacturers, equipment developers, steel producers, universities and leading technology centres: AZTERLAN (coordinator), CIE Legazpi, Fundación CIE I+D+i, Industrie-Ofen-Bau (IOB), BETSAIDE, Tecnodelta, RWTH Aachen University, SIDENOR, SIDENOR I+D, Energy Efficiency in Industrial Processes (EEIP) and AGH University of Krakow.
GREENLINE is funded by the European Union under the Horizon Europe programme as a HORIZON Innovation Action (Project No. 101294375), within the HORIZON-CL4-2025-01 call, specifically HORIZON-CL4-INDUSTRY-2025-01-TWIN-TRANSITION-34, which supports the twin green and digital transition of Europe’s energy-intensive industries.
