Opticast Ab

Cgi-promotion Ab

Lennart B&auml;ckerud

Guocai Chai

Lars Arnberg

The invention relates to a method of producing objects of cast iron containing compacted (vermicular) graphite crystals, by preparing a cast iron melt having substantially a carbon content at the desired final level and a silicon content below the desired final value, so that the equilibrium temperature (TE) for the reaction between carbon and SiO falls near 1400&deg; C., and adjusting the temperature of the melt (TM) to a value between the equilibrium temperature (TE) and the &ldquo;boiling temperature&rdquo; (TB), to allow absorption of oxygen by the melt to a level exceeding the desired level at the time the melt is poured into a mold, adding the required amount of silicon, and thereafter reducing the oxygen content by addition of magnesium or magnesium containing material, preferably a FeSiMg-alloy to an oxygen level of 10 to 20 ppm oxygen in liquid solution, and forming particles of magnesium silicates as well as cast objects obtained by the method.

Method to produce compacted graphite iron (CGI)

The present invention is a method for producing an iron-containing hypoeutectic alloy free from primary platelet-shaped beta-phase of the Al,FeSi in the solidified structure by the steps (a) providing an iron-containing aluminum alloy having a composition within the following limits, in weight percent, 6-10% Si, 0.05-1.0% Mn, 0.4-2% Fe, at least one of 1) 0.01-0.8% Ti and/or Zr 2) 0.005-0.5% Sr and/or Na and/or Ba, 0-6.0% Cu, 0-2.0% Cr, 0-2.0% Mg, 0-6.0% Zn, 0-0.1 % B balance aluminum (b) controlling and regulating precipitation path during solidification such that the precipitation of Fe containing intermetallic phases starts with the precipitation of the hexagonal phase of the Al,Fe,Si by (b1) controlling the condition of crystallization by addition of one or more of Fe, Ti, Zr, Sr, Na and Ba within the limits specified in step (a) and (b2) identifying the phases or morphology of the phases that precipitates during the solidification and correct the addition one or more times in order to obtain desired precipitation path and (c) solidifying the alloy at the desired solidification rate.

Growing community of inventors

Stockholm, Sweden

Lennart Bäckerud

Growing community of inventors

Stockholm, Sweden

Lennart B&auml;ckerud

Lennart Bäckerud