� TECHNOLOGY �
practices, there is a growing emphasis on using scrap-based and hydrogen-reduced steel. These new methods aim to reduce the carbon footprint of steel production, but it is crucial to ensure that the resulting steel has the same properties as traditional steel made from iron ore.
The LUS-based grain size gauge plays a vital role in this verification process. By providing accurate measurements of the steel’ s microstructure, it ensures that the new, greener steel meets the required standards. This capability is essential for gaining industry acceptance and driving widespread adoption of sustainable steel production methods.
Real-World Applications and Benefits
The LUS-based grain size gauge has already been installed and tested in the SSAB mill in Borlänge, Sweden. The system has demonstrated its ability to provide reliable measurements in the harsh environment of a hot strip mill. The gauge’ s robust design includes optics for a long working distance of more than half a meter and suitable protection against the harsh conditions.
In practical terms, the gauge offers several benefits:
• Enhanced Quality Control: By monitoring the grain size
in real-time, the gauge helps data provided by the gauge identify deviations in the can be used to develop new production process, allowing alloying concepts and to for immediate adjustments improve existing materials, and ensuring consistent and materials models, quality. For some steel grades thus accelerating the pace the Hall-Petch relation can of innovation in the steel also be utilized to measure industry. the mechanical properties, facilitating mechanical data Conclusion over the entire length of the The new LUS-based grain size strip / coil without the need for gauge is a groundbreaking costly and time consuming technology that has the destructive testing while also potential to revolutionize increasing the yield. the steel industry. By
• Process Optimization: The providing real-time, accurate data collected by the gauge measurements of the steel’ s can be used to optimize the microstructure, it supports the production process, in both transition to greener production feed-back / forward control methods and ensures the loops as well as assisting the quality and consistency of setup calculation in between the resulting steel. As more strips leading to more steel companies adopt this efficient and cost-effective technology, we can expect to production. see significant advancements
• Accelerated Material in both the efficiency and Development: The real-time sustainability of steel and detailed microstructure production.
About the author
Mikael has a doctorate degree in Physics concerning all-fiber modulators for laser applications at the Royal Institute of Technology. He continued as a post-doc at Uppsala university working with diamond waveguides for medical applications. Since 2016 he has been active in the Material Analysis & Process Monitoring group at Swerim working with laser ultrasonics for microstructural characterization. For a more detailed and technical description on how the laser ultrasound based grain size gauge works please watch www. youtube. com / watch? v = ZOpXUAPhEv0 & t = 665s.
14 Green Steel World | Issue 17 | April 2025