TY - JOUR

T1 - Identification of secondary raw materials in mold powders and their melting behavior

AU - Marschall, Irmtraud

AU - Kölbl, Nathalie

AU - Harmuth, Harald

AU - Atzenhofer, Christina

PY - 2019

Y1 - 2019

N2 - Commercial mold powders use a limited number of main mineral constituents, but may differ significantly in chemical composition. The main mineral raw materials of specimens investigated here are quartz, fluorite and free carbon, as well as wollastonite and carbonates. The investigations revealed the use of secondary raw materials like blast furnace slag, fly ash, glass scrap and phosphorous slag as further components. Since the formation of cuspidine was one major point of interest, the influence of the silica source on its formation was identified. A replacement of wollastonite by blast furnace slag reduced the temperature of the first precipitation of cuspidine by about 100 °C; the dissociation of sodium carbonate was lowered by ~ 40 °C. The lowest temperature of the first Na 2 CO 3 dissociation could be achieved by using fluorine in combination with blast furnace slag. Cuspidine formation from the melt is further decreased if sodium and fluorine are both present. The use of glass scrap and phosphorous slag strongly reduced the temperature of first melt formation and enhanced cuspidine formation.

AB - Commercial mold powders use a limited number of main mineral constituents, but may differ significantly in chemical composition. The main mineral raw materials of specimens investigated here are quartz, fluorite and free carbon, as well as wollastonite and carbonates. The investigations revealed the use of secondary raw materials like blast furnace slag, fly ash, glass scrap and phosphorous slag as further components. Since the formation of cuspidine was one major point of interest, the influence of the silica source on its formation was identified. A replacement of wollastonite by blast furnace slag reduced the temperature of the first precipitation of cuspidine by about 100 °C; the dissociation of sodium carbonate was lowered by ~ 40 °C. The lowest temperature of the first Na 2 CO 3 dissociation could be achieved by using fluorine in combination with blast furnace slag. Cuspidine formation from the melt is further decreased if sodium and fluorine are both present. The use of glass scrap and phosphorous slag strongly reduced the temperature of first melt formation and enhanced cuspidine formation.

UR - http://www.scopus.com/inward/record.url?scp=85064349882&partnerID=8YFLogxK

U2 - 10.1007/s42243-019-00254-6

DO - 10.1007/s42243-019-00254-6

M3 - Article

VL - 26.2019

SP - 403

EP - 411

JO - Journal of iron and steel research international

JF - Journal of iron and steel research international

SN - 1006-706X

IS - 4

ER -