Abstract: The present invention refers to a vermicular cast iron alloy specially designed for internal combustion engine blocks and heads having special requirements of mechanical strength and fatigue strength. Vermicular iron alloy with high mechanical strength and high fatigue strength for the production of internal combustion engines blocks and heads characterized by having a microstructure of pearlitic matrix and predominantly vermicular graphite (>70%) and presence of graphite nodules in up to 30%, wherein its graphite microstructure is described by the Microstructure Factor (FM), as defined below, with Microstructure Factor values higher than 0.94.

Abstract: A process for producing spheroidal graphite cast iron includes a spheroidization treatment, an inoculant treatment and a pouring inoculation treatment. A molten iron is subjected to the spheroidization treatment using a spheroidizing agent of an Fe—Si—Mg—Ca-based alloy which contains a given amount of Ba and contains substantially no rare-earth element.

Abstract: A nodular graphite, heat-resistant cast iron composition for use in engine systems. The composition contains carbon 1.5-2.4 weight %, silicon 5.4-7.0 weight %, manganese 0.5-1.5 weight %, nickel 22.0-28.0 weight %, chromium 1.5-3.0 weight %, molybdenum 0.1-1.0 weight %, magnesium 0.03-0.1 weight %, and a balance weight % being substantially iron. The composition has an austenitic matrix. Additionally, the composition exhibits excellent oxidation resistance at high temperature and excellent mechanical properties at both room and high temperatures. Thus, the composition can be a lower cost substitute material for Ni-Resist D5S under thermocycling conditions experienced by exhaust gas accessories and housings such as engine exhaust manifolds, turbocharger housings, and catalytic converter housings.

Abstract: A nodular or compacted graphite iron contains up to 6% aluminum, with high strength and good ductility over a wide temperature range, combined with excellent hot oxidation resistance and improved thermal fatigue resistance compared to ductile and SiMo ductile irons. The iron alloy of the invention contains, in addition to iron, from about 1 to about 6% aluminum, from about 2 to about 4.5% silicon, carbon in an amount where the weight percent carbon plus ⅓ the weight percent of silicon is up to about 5.2%, greater than or equal to about 0.02% cerium and up to about 1.5% molybdenum. All percentages are based on the total weight of the composition. The compositions may further contain up to about 7% nickel by weight.

Abstract: A process of producing magnesium-treated iron such as spheroidal graphite iron (SGI), compacted graphite cast iron (CGI) containing inclusions that deform plastically during machining, said process comprising the steps of: a) producing base iron; b) desulfurizating the base iron produced in step a) with a magnesium free reagent, if it is sulfur concentration exceeds 0.02 % (wt.); c) controlling the oxygen potential and temperature of the base iron to facilitate silicon control of oxygen, if the amount of oxygen exceeds 10 ppm; d) adding aluminum, calcium and/or calcium-containing oxides to the base iron in amounts designed to form dicalcium aluminate deoxidation product or low melting point calcium aluminum silicate deoxidation product; e) treating the base iron with magnesium containing inoculant to attain desired condition for desired nodularity; and f) continuing the process of producing magnesium-treated iron in a per se known manner.

Abstract: A treatment agent and method to introduce magnesium into ferrous material. The treatment agent includes a mixture of high melting temperature particles and magnesium particles. The content of high melting temperature particles in the particle mixture is present in an effective amount to inhibit the complete conversion of the magnesium particles into molten magnesium prior to the magnesium particles entering the ferrous material. The method describes the efficient treatment of molten ferrous material with these particles.

Abstract: The invention relates to a process for producing nodular cast iron with a high number of graphic nodules. This process comprises the following steps: preparing molten base iron for casting castings of nodular cast iron; adding Mg to the molten base iron; inoculating the casting stream with a first inoculant when casting the cast iron into a casting mould. According to the invention, between the addition of the Mg and the inoculation of the casting stream, a preliminary inoculation using a further inoculant is carried out as an additional step.

Abstract: Disclosed is a process for desulphurization of a pig iron melt for further processing wherein the melt is brought into close contact with a ground solid slag. As desulphurizing agent, the slag accumulating in secondary steelmaking with a basicity of at least 4, an iron content in the range of 4 to 6 wt.-% and a phosphorous content in the range .ltoreq.0.4 wt.-%, is used in ground form or the slag is used together with calcium carbide and magnesium as a solid mixture in ground form.

Abstract: The present invention provides an inoculation wire consisting of a hollow wire, containing powdered ferrosilicon, with a sheeth of steel, copper, nickel or aluminum alloy, for the production of cast iron with spheroidal graphite or vermicular graphite, wherein the filling contains 1 to 50% by volume of powdered magnesium silicide.

Abstract: Conventionally, heat treatment was necessary in the final stage of producing nodular cast iron products to give the nodular cast iron with desired mechanical properties. This was necessary because of the loss of graphitization capability of the molten metal when it is being formed into nodular cast iron during the process of spheroidization, and the heat treatment is therefore required to decompose cementite formation and thereby promote graphitization. The process of producing nodular cast iron according to the present invention can achieve the promotion of graphitization and the increase in the number of graphite nodules, which are both important for the production of high-quality thin-shell cast iron products, through the synergetic effect of processing the molten metal with a graphitization agent such as SiC or CaC.sub.2 and of adding a graphite atomization agent such as Bi.

Abstract: In a process of producing nodular cast iron wherein molten cast iron is treated in two stages with elements for inducing a formation of a predominantly nodular graphite, the crystallization of the graphite and the dynamic properties of the casting are improved in that a rare earth metal is added to the molten cast iron in the first treating stage and magnesium metal or a magnesium-containing master alloy in an amount which is sufficient for the formation of a predominantly nodular graphite is added to the molten cast iron in the second treating stage, in which no RE metal is added to the molten cast iron. The treatment is particularly effected with sheathed wires consisting of a steel sheath around a core of treating agent powder.