The effects of ultrasonic treatment (UST) on the solidification microstructure of a 35CrMo steel cast ingot were investigated. To avoid the erosion of a high-temperature melt, a T-shaped ultrasonic waveguide unit was used to introduce ultrasonic vibrations into a 35CrMo steel die casting melt. The experimental results show that the microstructure of the ingot was refined by ultrasonic treatment...

F. Tehovnik, J. Burja, B. Arh, Institute of metals and technology, Ljubljana, Slovenia, M. Knap, University of Ljubljana, Faculty of Natural Sciences and Engineering, Ljubljana, Slovenia Nozzle clogging is a common problem in the production of continuously cast Al-killed steels. Clogging occurs when there are solid inclusions in molten steel at casting temperatures. SENs (Submerged entry nozzle...

An NbC-Fe composite powder was synthesized from an Nb₂O₅/Fe/C mixture by electrochemical reduction and subsequent carbonization in molten CaCl₂-NaCl. The composite has a core-shell structure, in which NbC acts as the cores distributing in the Fe matrix. A strong bonding between NbC and Fe is benefit from the core-shell structure. The sintering and electrochemical reduction processes were invest...

background numerous factors have an effect on the accuracy of an impression and resultant cast, and these include: impression material, impression technique, tray selection, impression disinfection, storage time of impression before pouring, stone type used for fabrication of cast. up to now, there has been little research conducted on the effect of contact time of a cast with an impression, on...