عنوان مقاله [English]
Semi-solid metal forming offers many advantages in comparison with conventional casting and forging. However, due to the high-melting temperature and related difficulties, there is relatively a few experimental data on the semi-solid processing of steels. Therefore, this study is subjected to the microstructure evolution during partial remelting of 304 stainless steel which is pre-deformed in solid state by a severe plastic deformation (SPD) technique. Thermodynamic calculations were carried out by Thermo-Calc software and the results were compared with the experimental observations. In this study, repetitive corrugation and straightening by rolling (RCSR) process as a new severe plastic deformation technique is utilized to induce a great amount of strain in material prior to semi-solid process. Microstructural evolutions were studied in different temperatures and holding times during semi-sold process. The results indicate that finer globular semi-solid microstructure is achieved from 30 cycles RCSR processed specimen after 3 minutes holding at 1425 ℃.
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