Research of semi solid casting of iron

Microstructural evolution and flow stress of semi-solid type 304 stainless steel

“…It can be pointed out that the semi-solid forming technology has already achieved commercial status, mainly in the field of manufacturing wheels or other automotive components [10]. However, there are only a few researches and applications of semi-solid forming of metals with higher melting point and alloys such as steels, because of its high working temperature, narrow semi-solid temperature interval and complicated phase transformation during solidification and re-melting [11,12]. Although, the steels with higher alloying elements have wider range of solidification temperature, it is only about 60 K for type 304 stainless steel [13], which is only a half of that for aluminum alloys.…”

Semi-solid rolling process of steel strips

“…Under the condition of electromagnetic stirring, intense convection occurs in liquid, resulting in the change of growth condition of crystals. The primary grains will not grow in dendrite form, but grow in non-dendritic form, similar to sphere shape (Ichikawa et al, 2002;Tsuchiya et al, 2003;Robert et al, 2002;Song et al, 2002). Compared with Fig.…”

“…Several companies in Europe, Japan and the US have started to manufacture in this technique, producing millions of components annually for motor industry (Chen et al, 2002;Margarido and Robert, 2003;Chiarmetta, 1998;Jung et al, 2001;Iwasaku et al, 1998;Nohn et al, 2000). In the application of SSF technique, at present, it is mainly used to produce the low melting point alloys such as Al-base, Zn-base and Mg-base alloys (Watari et al, 2004;Haga, 2001;Cook et al, 1995;Ichikawa et al, 2002;Tsuchiya et al, 2003;Robert et al, 2002;Song et al, 2002 , 2001;Seidl et al, 2002;Meuser and Bleck, 2001;Choi and Park, 1998;Seo and Kang, 2005), but the high melting point alloys, for example iron and steel as the most widely useful metal are not extensively studied and applied. Their SSF technique has a great difference from that of the low melting point alloys, for example: (1) the region size of liquid and solid phases coexisting for many steel alloys is smaller;…”

“…Few investigations were made in the semi-solid forming of steels, such as spring steel and stainless steel (Haghayeghi et al, 2005;Li et al, 2005). Different methods have been used to fabricate steels with non-dendritic structures, such as electromagnetic stirring, partial re-melting and ultra-refining using inoculants (Tsuchiya et al, 2003;Li et al, 2005). The present work used the electromagnetic stirring method to obtain semi-solid slurry.…”

“…The overall homogenization of the macrostructures in the whole part of steel ingot can be achieved. Therefore, comparing to the twin-roll strip casting process (Watari et al, 2004;Haga, 2001;Cook et al, 1995;Ichikawa et al, 2002;Di, 2005;Bao et al, 2003), they have beneficial effects on microstructure of product such as reducing segregation, improving inclusion size distribution and refining microstructural and textural homogeneity (Tsuchiya et al, 2003;Robert et al, 2002;Song et al, 2002;Kang et al, 2001;Seidl et al, 2002;Meuser and Bleck, 2001;Choi and Park, 1998;Seo and Kang, 2005;Di, 2005;Bao et al, 2003).…”