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Automation of the iron and steelmaking operations is an inevitable task to improve quality and to minimise cost. Recent studies showed that vibroacoustic-based monitoring techniques can be used to continuously monitor steelmaking processes. Various signal processing techniques have been used, including filtering and FFT, to process these signals into useful inputs for process control. In ironmaking, the acoustic noise has been studied to assess working conditions. Vibration and acoustic signals have been measured in oxygen steelmaking to evaluate slopping. Lance vibration has been used to automate the blowing process at Kawasaki Steel Corporation. In ladle metallurgy, the focus has been on developing a vibroacoustic method to monitor liquid metal stirring. Recent water model studies have identified how sensor placement and the depth of the slag phase affects these signals. There has also been a work to monitor slag carry over in tundish metallurgy using vibration. These applications can be extended to other steel producing processes in the industry.

The stirring power required achieving uniform composition and temperature in ladle metallurgy is a function of the volumetric gas flow rate, metal depth, and slag thickness. Accurate estimation of the stirring power requires the precise determination of the amount of metal and slag depth. The present study found that frequencies of the acoustic signal generated during the stirring process can indicate the depths of metal depth as well as slag thickness. This is promising as it offers a potentially simple technique for simultaneously detecting slag thickness and stirring in ladles.

Increasing temperature is one of the key factors for improving the efficiency of steam power plants. Important metallurgical phenomena are activated at such high temperatures and creep resistance becomes a driving criterion for the material selection. Ferritic steels, including 2Cr, 9Cr, and 12Cr steels, are among the best candidates; their continuous development and optimization with the addition of Mo, V, Nb, and W have resulted in a significant improvement in creep strength together with a good weldability. This study investigates the high-temperature mechanical properties of two Grade 91 welded plates and focuses on the creep behavior, proposing a modified expression of the Larson–Miller parameter for the estimation of critical combinations of temperature, stress, and time, which could lead to rupture. The suggested parameter, which is highly sensitive to temperature, is able to outline the criticality of the welding and it is useful for predicting the duration of a creep test with the specimen rupture.