Modification of Non-Metallic Inclusions by Rare-Earth Elements in Microalloyed Steels

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Modification of Non-Metallic Inclusions by Rare-Earth Elements in Microalloyed Steels

The modification of the chemical composition of non-metallic inclusions by rare-earth elements in the new-developed microalloyed steels was discussed in the paper. The investigated steels are assigned to production of forged elements by thermo-mechanical treatment. The steels were melted in a vaccum induction furnace and modification of non-metallic inclusions was carried out by the michmetal in the amount of 2.0 g per 1 kg of steel. It was found that using material charge of high purity and a realization of metallurgical process in vacuous conditions result in a low concentration of sulfur (0.004%), phosphorus (from 0.006 to 0.008%) and oxygen (6 ppm). The high metallurgical purity is confirmed by a small fraction of non-metallic inclusions averaging 0.075%. A large majority of non-metallic inclusions are fine, globular oxide-sulfide or sulfide particles with a mean size 17 μm2. The chemical composition and morphology of non-metallic inclusions was modified by Ce, La and Nd, what results a small deformability of non-metallic inclusions during hot-working.

Wypartowicz J., Podorska D. (2006). Control of chemical composition of oxide-sulfide inclusions during deoxidation of steel with manganese, silicon and titanium. Metallurgy - Metallurgical Engineering News. 3, 91-96 (in Polish).

Oikawa K., Ishida K., Nishizawa T. (1997). Effect of titanium addition on the formation and distribution of MnS inclusions in steel during solidification. ISIJ International. 37, 332-338.

Ishikawa F., Takahasi T., Ochi T. (1994). Intergranular ferrite nucleation in medium-carbon vanadium steels. Met. Materials Transaction A. 25A, 926-936.

Gladman T. (1997). The Physical Metallurgy of Microalloyed Steels, University Press Cambridge.

Adamczyk J. (2004). Engineering of Metallic Materials. The Silesian University of Technology Publishers. Gliwice (in Polish).

Kiessling R. (1997). Lange N. Non metallic inclusions in steel. The Institute of Materials, London.

Lis T., Nowacki K., Kania H. (2001). Improvement of steel purity by ladle metallurgy. Metallurgy - Metallurgical Engineering News. 10, 356-361 (in Polish).

Bolanowski K. (2004). Effect of rare-earth elements addition on structure and properties of steel. Metallurgy - Metallurgical Engineering News. 7-8, 323-325 (in Polish).

Grajcar A. (2010). Modification of non-metallic inclusions by rare-earth elements in low-alloyed C-Mn-Si-Al type steels. Ores and Non-Ferrous Metals. 3, 143-152 (in Polish).

Grajcar A., Galisz U., Bulkowski L. (2011). Modification of non-metallic inclusions by rare-earth elements in high-manganese austenitic C-Mn-Si-Al type steels. Metallurgy - Metallurgical Engineering News. 2, 178-187 (in Polish).

Garbarz B., Żak A., Wojtas J., Molenda R. (1999). The effect of fine particles of nonmetallic inclusions of the austenite grain growth in microalloyed steels. Material Engineering. 1, 5-12 (in Polish).

Garbarz B. (1995). The effect of some continuous casting parameters and microalloying elements on the effectiveness of controlling of austenite grain size. Journal of Materials Processing Technology. 53, 147-158.

Garbarz B., Marcisz J., Wojtas J. (2003). TEM analysis of fine sulfides dissolution and precipitation in steel. Materials Chemistry and Physics. 81, 486-489.

H. Kejian, T. N. Baker (1992). Copper containing sulfide phases present in controlled rolled niobium-titanium bearing high strength low alloy steels, Materials Science and Technology, 8 1082-1089.

Shim J., Oh Y., Suh J., Cho Y., Byun J., Lee D. (2001). Ferrite nucleation potency of non-metallic inclusions in medium carbon steels. Acta Materiala. 49, 2115-2122.

Shim J., Cho Y., Chung S., Lee D. (1999). Nucleation of intergranular ferrite at Ti2O3 particle in low carbon steel. Acta Materiala. 47, 2751-2760.

Vainola R. V., Holappa L. E., Karvonen P. H. (1995). Modern steelmaking technology for special steels. Journal of Materials Processing Technology. 53, 453-465.

Wolańska N., Lis A. K., Lis J. (2007). Investigation of C-Mn-B steel after hot deformation. Archives of Materials Science and Engineering. 28, 119-125.

Wolańska N., Lis A. K., Lis J. (2007). Microstructure investigation of low carbon steel after hot deformation. Journal of Achievements in Materials and Manufacturing Engineering. 20 (1-2), 291-294.

Archives of Foundry Engineering

The Journal of Polish Academy of Sciences

Journal Information

CiteScore 2016: 0.42

SCImago Journal Rank (SJR) 2016: 0.192
Source Normalized Impact per Paper (SNIP) 2016: 0.316

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