Martensite/retained austenite, or M/A, is a second-phase constituent in the microstructure of steel. M/A has been observed in steel products processed through different routes. M/A constituent has a strong effect on the mechanical properties of steel. Understanding its effect is very important in order to avoid any negative impact on the performance of steel. In this article, the effects of M/A on the mechanical properties of several micro­alloyed steels will be discussed.

The continuous improvement of hot strip rolling technology and the development of new steel grades make it necessary to use specialized models of hot rolling mills in order to successfully produce high-quality products. Examples of such technologies can be Compact Strip Production (CSP® by SMS group), Endless Strip Production (Arvedi ESP by Primetals Technologies) and Quality Strip Production technology (QSP® by Danieli). Moreover, the availability of such models makes it possible to accelerate the testing of new steel grades through virtual trials. Virtual trials allow saving costs in the process of finalizing steel composition. This article summarizes successful experiences of United States Steel Corporation in development such models and their usage.

Selecting the appropriate cooling method for slabs after continuous casting is crucial for both slab quality and processing time, which is important for meeting shipment deadlines. While intense cooling may reduce processing time, it can also affect the steel’s microstructure and potentially lead to crack formation. In this study, criteria for determining the slab cooling method (e.g., forced cooling, common pile, sandwich pile, or hood cooling) was developed based on the steel grade composition, using a machine learning technique.

The Danieli MultiPlate is a single facility that can produce wide heavy plates, light discrete or coiled plate with yield strengths up to 1,800 MPa. It is configured in a layout that can process both ingots and slabs, can make straight or cross-rolling and can roll in flat as well as Steckel mode. The plant configuration includes Danieli equipment for in-line quenching and a multipurpose leveler to cover a product portfolio to serve the construction, energy, oil and gas, mining, and defense industries. The latest installation at Nucor Steel Brandenburg establishes a new benchmark in plate production worldwide.