Abstract: A sampling device for thermal analysis of solidifying metal is disclosed. The sampling device comprises at least a first cavity and a second cavity, the first and second cavities adapted to be filled with a molten metal to be analysed and each cavity adapted to comprise a temperature responsive means during thermal analysis. The inlet opening of the common filling inlet is arranged in a second plane essentially parallel to a first horizontal plane tangent to an uppermost portion of the sampling device and located below said first plane.

Abstract: A sampling device comprises a container having an essential cylindrical part and a bottom part. The container further comprises an inner wall member and an outer wall member. The inner wall member and the outer wall member are essentially coaxially arranged in the cylindrical part of the container and joined at the top part of the container, and the inner and outer wall members define a closed insulating space between the outer surface of the inner wall member and the inner surface of the outer wall member. The sampling device further comprises temperature responsive means adapted to extend into the sample quantity during thermal analysis. Spacer means is arranged in the insulating space in the bottom part of the container and/or in the cylindrical part of the container in the vicinity of the bottom part.

Abstract: A composition for coating of a surface intended to be exposed to a metal melt consists of 8-18 wt-% of a refractory component, 50-75 wt-% of solvent, preferably water, 10-20 wt-% of an inorganic binder, 0-10 wt-%, preferably 2-10 wt-%, of an organic binder, 0.3-7 wt-%, preferably 2-6 wt-%, more preferably, 3-5 wt-% of pyrite; and optionally up to 10 wt-%, preferably up to 5 wt-%, of additional additive or additives. The composition results in a coating on a surface, which coating is able to reduce the dissolved elemental magnesium content in a metal melt to which the surface is exposed.

Abstract: The composition for coating of a surface intended to be exposed to a metal melt is disclosed. The composition essentially consists of: 8-18 wt-% of a refractory component; 50-75 wt-% of solvent, preferably water; 10-20 wt-% of an inorganic binder; 0-10 wt-%, preferably 2-10 wt-%, of an organic binder; 0.3-7 wt-%, preferably 2-6 wt-%, more preferably, 3-5 wt-% of pyrite; and optionally up to 10 wt-%, preferably up to 5 wt-%, of additional additive or additives. The composition results in a coating on a surface, which coating is able to reduce the dissolved elemental magnesium content in a metal melt to which the surface is exposed.

Abstract: The present invention provides a sampling device for thermal analysis of molten metal, in particular molten cast iron, said sampling device being intended to be filled with liquid metal to be analysed, said sampling device being a container having an upper side and a lower side, said container comprising one common filling inlet on the upper side of said container and at least two cavities, each cavity having a protective tube adapted for enclosing a temperature responsive sensor member, characterised in that said common filling inlet is branched into at least two filling channels ending in said cavities. The invention also provides a kit of parts intended for thermal analysis of solidifying metal, said kit comprising a temperature responsive sensor means and a sampling device as disclosed above.

Abstract: The present invention provides a novel method and a system of modules for carrying out thermal analysis of cast iron melts. The characterizing step of the method is de-termination of the position of the thermocouples used for recording cooling curves. The system comprises a thermocouple unit, a thermocouple holder, and a sampling unit. The system comprises means for ensuring that the thermocouples are correctly positioned before starting the thermal analysis. The system also comprises means for automatically transferring calibration data regarding the thermocouples.

Abstract: It is possible to generate a desirable form (soft, pliable) of sulfide inclusions in magnesium-treated case irons. Thermodynamically, MnS and MoS2 are not stable in the presence of magnesium. However, by adding magnesium to a cast iron melt containing manganese sulfide/molybdenium sulfide as late as possible, and preferably when the molten cast iron has been dispensed into the mould, such sulfide inclusions may be preserved in magnesium-treated cast iron. Alternatively, said cast iron can also be formed by adding said sulfides directly to the iron after the magnesium reaction has taken place and an in situ equillibrium has been established between magnesium, oxygen and sulfur. Another option is to begin with a sulfur content in excess of the stoichiometric amount required to combine with the added magnesium, thus ensuring an amount of left-over sulfur to promote the formation of the desired sulfide inclusion.

Abstract: The present invention provides a possibility to evaluate cooling curves recorded in near-eutectic cast iron melts. The curves are evaluated by generated in the melt in the center of the sample to the melt as a function of time. This information is then used to identify the part of the centrally recorded cooling curve that can be used as a basis for determining the amount of structure-modifying agent that must be added to produce compacted graphite cast iron, and/or spheroidal graphite cast iron, and to identify the part of said curve that is associated with formation of primary austenite.

Abstract: A sampling device for thermal analysis of solidifying metal, particularly compacted graphite iron, includes a container (2) essentially cylindrical, open at the top intended to be immersed down into and filled with a liquid metal to be analyzed, at least one temperature responsive sensor member (4), preferably two, a protective tubing (14) concentrically enclosing said sensor(s), arranged inside said container (2) and supported by a sensor support member (15) arranged above said container and attached to the container (2) by legs (16) and intended to guide and keep the sensors (4) in position, when immersed in the solidifying metal sample quantity (3) during analysis, wherein container (2) has an interior surface (17) intended to contact the sample quantity (3) during analysis, and an exterior surface (18) intended to contact the ambient atmosphere, the surfaces (17 and 18) being joined at the mouth (12) of the container (2), being equally spaced forming a closed insulating space (8), and the container (2) ha

Abstract: A process for producing a compacted graphite iron (CGI) article, comprising the steps of: (a) providing a CGI base iron having a composition comprising, in weight percentages, about 3.2 to 3.8 total C, 2.8 to 4.0 Si and the balance at least Fe and incidental impurities; (b) treating, controlling and casting the alloy in a manner known per se; (c) allowing the cast component to cool in the mould to a temperature of at least 775° C.; (d) cleaning the casting in a manner known per se and machining the casting to produce a finished article.

Abstract: The invention provides a cast iron alloy comprising 3.0-3.8% carbon, 06-25% silicon, 0.2-0.65% manganese, 0.01-0.1% tin, <0.025% sulfur, 0.001-0.020% magnesium, 0.1-1.2% copper, 0.04-0.2% chromium, and balance up to 100% of iron and incidental impurities. The matrix structure is a continously variable ferrite/pearlite mixture and the content of carbides is less than 1%. The graphite shape of the alloy is 1 50% flake graphite, 50-99% compacted graphite and at most 10% spheroidal graphite. Such an alloy is easier to machine and less prone to shrinkage than an ordinary compacted graphite cast iron.

Abstract: A sampling device for thermal analysis of solidifying metal, comprising at least one container intended to contain a sample quantity (30) of liquid metal during analysis, and at least one sensor (40, 220, 240) for thermal analysis, said sensor(s) being intended to be at least partly immersed in the solidifying metal sample quantity during analysis. The container comprises an inner wall (50), with an interior surface (60) intended to face the sample quantity during analysis, and an exterior surface (70); an outer wall (80), with an exterior surface (100) intended to face the ambient atmosphere, and an interior surface (90); said walls being joined at the mouth of the container whereby the exterior surface (70) of the inner wall (50) and the interior surface (90) of the outer wall (80) together define an essentially closed space (110).

Abstract: By studying heat transfer in a sample vessel containing a sample of molten cast iron, it is possible to carry out accurate predictions of the microstructure in which the molten cast iron sample will solidify. This method is also highly suitable for automatisation by using a computer.

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 method for measuring the melt temperature in a melt vessel, where the vessel wall, at least partially, is made of a material transparent for infrared light; said material, at the interior of the vessel, is coated with a material having a high and stable emission factor (e>0.5; de/dT<0.001); the temperature of the inside of the vessel wall is used as a measure of the melt temperature close to the wall; and said temperature at the inside of the vessel wall is measured by use of optical pyrometry applied from the outside of the melt vessel.

Abstract: A method for controlling the composition of a cast iron melt is presented. A cast iron melt is prepared which has added to it a structure modifying agent and a nucleating agent in amounts selected to produce a fully compacted graphite iron upon solidification of the melt. A sample vessel, having an inner wall having an active portion coated with a material which will lower the concentration of dissolved modifying agent and an inert portion, is used to extract a sample of the melt. Three temperature measuring devices are used to measure temperatures at three locations within the melt. One measuring device measures the temperature at the center of the vessel, one measures the temperature at the inert portion of the vessel's inner surface and one measures the temperature at the active portion of the vessel's inner surface. In another aspect of the invention, two sample vessels are used, one having an active surface and the other having an inert surface.

Abstract: A method for producing metal castings comprising the steps of: i) providing a conditioning furnace, having an inlet channel and an outlet channel, with pre-treated molten metal; and ii) reducing the height of molten metal in the outlet channel to a level (h.sub.1) lower than the level of the molten metal in the conditioning furnace (h.sub.0) such that the molten metal in the spout and in the outlet channel, at least partly, is brought back into the furnace body where it can be recharged with a nucleating and/or structure modifying agent, iii) adding further nucleating and/or structure agent to the molten metal when necessary, iv) mixing the melt in the furnace when necessary and v) after the stoppage, casting the melt with the desired content of structure modifying agent.

Abstract: A sampling device for use when performing a thermal analysis of a sample of molten metal solidifying from a melt, includes a double-walled container having an upwardly opening mouth and a part-spherically curved bottom, A closed space between the walls is thermally insulated. A tubular holder is supported to extend from the mouth substantially to the bottom of the container, for receiving a temperature sensor. By preference at least one wall of the container is treated or coated to reduce thermal emissivity.

Abstract: The surface tension of a sample quantity of molten iron from a batch of molten iron is determined and compared with the surface tension of the sample with the surface tensions of batches of molten iron that are known to solidify as respective different forms of cast iron. The surface tension of the molten iron sample is determined by adding the sample to a sample cup, submerging a device for introducing a noble gas into the molten iron of the sample, positioning a piezoelectric transducer at the bottom of the sample cup, administrating the noble gas at a constant rate through the device, measuring the temperature of the sample, and monitoring vibrations in the molten iron of the sample by recording signals from the transducer.

Abstract: A method for continuously providing pretreated molten iron for casting objects which solidify as compacted cast iron, in which inoculating agents are added immediately prior to casting, in exact quantities. In practicing the method, the ability of the fully treated cast iron to crystallize is measured and the result of this measurement is used for feedback control of the supply of inoculating agent, this supply being effected at the last possible stage of the treatment process, so as to optimize the amount of inoculating agent introduced to the system. Since the inoculating a gent will normally include FeSi, it will also fed back and used to increase or reduce the addition of agents for adjusting the carbon and/or silicon contents of the iron as necessary.