METAL METAL SILICATE MATERIAL

The invention concerns a metal metal silicate material, in particular for the employment at high temperatures. A typical use of such materials are nozzles for the production of continuous casting profiles made of metal and for the extrusion of bar and tubes of different cross sections made of metal. At present graphitic nozzles are used for the continuous casting of metal seaweeds. Their insusceptibility against thermal shock is good, the thermal conductivity lies near the necessary range and it is relatively cheap in the production. Because of the high wear speed its service life is however short, which leads to changes of the dimensions and the surface of the bars. Another material is described by the metal works plan lake AG., in its Australian patent specification Nr.402886. There it concerns a Cermet, whose Keramlkkomponente is zircon oxide (Zyrkon grounds) and its metal component molybdenum and/or tungsten, whereby chrome is added to the metal phase. In some Fä31en the stabilization of the ceramic phase happens through for example calcium oxide and magnesium oxide. Such Cermets stand for continuous casting nozzles an improvement opposite graphite, but are them relatively expensive and for a nozzle construction justified only if a long service life of the nozzle can be expected. A long service life seems however improbably, since fusionliquid iron has the tendency to attack Cermets of this kind even if a high zirconia portion comes to the use. The invention sits down the creation of an improved and cheaper material £ ' ür to nozzles for continuous forming of staff material, tubes and the like out of metal to the goal. It turned out that one can achieve these goals with a metal metal silicate material, in which the zircon oxide of the well-known material by zircon silicate is replaced. From such a material manufactured nozzles are hardly attacked by schrnelzflüssigem iron after longer use. The material according to invention is characterized thereby that the metal silicate component is zircon silicate and the metal component one of the elements molybdenum, tungsten, silver, copper or a Silb he palladium alloy. Is met 111 if che component molybdenum or tungsten, then the zircon silicate is generally in a quantity from 7 to 84 Gew. - % available. If the metallic component is however silver, copper or a silver palladium alloy, then the zircon silicate is generally in a quantity from 50 to 92Gew. - % available. The metallic component whether now molybdenum or tungsten knows, also chrome contained in a quantity of up to 10 Gew, o%. Such metal metal silicate materials can be manufactured in each suitable technical procedure. In typical cases they are sintered from compressed, powdered silicate and MetaU either hot-pressed or, whereby the latter method requires somewhat higher temperatures, since no continuing pressure is present, which could support the compression of the material. A characteristic of the invention lies that in the new, materials according to invention those up to now as suitably well-known metals, i.e. molybdenum and [or tungsten, also by silver, a silver Palladinm Leglerung or copper to be replaced can. One could mean that silver is a metal unsuitable for this purpose, since its Schrnelzpunkt is generally under that one of the fusionliquid metals, which are to be formed with the help of the nozzles out of the erfindnngsgemäßen material, but has silver a high heat conductivity, silver increased from there the speed of the Wärmeentznges made of the hot metal and makes in such a way containing nozzles more insensitively to thermal shock. A further advantage of silver consists of that it does not oxidize. Since silver, silver Palladinm alloys and copper have high thermal expansion numbers and relatively low fusion points, they can be built in the material according to invention only with small Volumenverhältnissen. Under these circumstances is wässrigkeit the metal metal silicate body to the co-operation of the zirconium silicate to attribute, and the heat conductivity of this material can be lower than with a material with molybdenum or tungsten. Depending upon the available requirements it could be necessary from there to lower the wall thickness of a nozzle or a nozzle zone, which a Meta21-Metallsilikat-Material with silver, copper or silver Palladinm contains, so that the necessary Wärmeteitung develops. Despite the low fusion points of silver, silver palladium alloys and copper metal metal silicate materials with these metals and/or alloys or a mixture from it can be dipped as metal phase long time into 1390°C hot fusionliquid cast iron, without experiencing practically any change from form and “surface to; in addition the decrease in weight is negligible. In case of a material with molybdenum or tungsten one can the metallic phase chrome in a concentration up to 10 Gew. - add % of the metal component to lower in order to stick the tendency of the fusionliquid metals, to the metal metal silicate material. Such an additive causes a layer from chrome oxide, which works against the adhesion of the schrnelzflüssigen metal at the surface. Molybdenum oxide would have the same effect, is however at the temperature of most fusionliquid metals volatile, so that a fresh metallic molybdenum surface would always opposite-stand for the melt. In the following examples are stated by according to invention designed ceramel bodies. B e i s p i e I 1: Into a form for a strand casting nozzle a feingemahlene mixture became from 20 Gew. - % zircon silicate and 80 Gew. - % molybdenum assigned and under a pressure of 245 kp/cm2 on 1500°C heats up. After cooling under pressure in such a way formed nozzle as well as a similar nozzle, whose ceramic phase was zircon oxide, was dipped with 1390°C two hours long into fusionliquid iron. To the Eutnahme from this bath points oneself on the surface with zircon silicate of the gesture of! lten nozzle only negligibly little scale, against what those zircon oxide containing nozzle a Gewlchtsverlust of 30 Gew. - % had suffered. In the following use of this nozzle from Meta Metallsilikat with zircon silicate poured Eisenstabprof'ile showed a wear of the nozzle of less than 0.0166 mm per 100 m; this wear is not more highly smaller as with nozzles from Cermets with zircon oxide and more as 20-20-mal than with graphitic nozzles. An investigation of the work surface of the nozzle with zircon silicate did not show a provable degradation. B e i s p i e 1 2: It became a nozzle in the same way as in example 1 using a metal metal silicate mixture from 8 Gew. - % silver and 92 Gew. - % zircon silicate manufactured. The material was immersed two hours long into fusionliquid cast iron with 1390°C. After taking out of this bath the material was unchanged; the original sharp corners were still present. B e i s p i e 1 3: A finely gematdene mixture from tungsten metal and zircon silicate with a content of 11 Gew. - % silicate was heated up in a form under a pressure by 245 kp/cm2 on 1500°C. In such a way formed material was dipped two hours long into 1390°C hot cast iron. The attack was slight compared with that one of a Cermets from molybdenum/zircon oxide in the same Gewichtsverhäknis. B e i s p i e I 4: It was consisted those of metal metal silicate materials, of mixtures of molybdenum and Zirkensilikat, a fourth-hasty nozzle was manufactured. The parts and/or sections were arranged after increasing ruggedness against fusionliquid iron, however removing Wärmdeitfähigkeit. The content outer zircon silicate in the four sections was in sequence 11, 21, 31 and/or 48 Gew. - %, whereby the section with the highest content was because of zircon silicate at the hot end. After the production of 2100 m poured staff cross section the nozzle worked still perfectly, with only slight changes of the dimensions and the surface quality. A typical graphitic nozzle had an entire life span of between 150 and 300 m, whereby with 150 m a dimension change from 0.5 mm was to be already observed to. E e i s p i e 1 5: A fourth-hasty nozzle was manufactured as with example 4, only the section with 48 Gew became. - % zircon silicate by a Abzugstefl replaces, the 89 Gew. - % Zlrkonsilikat and 11 Gew. - % silver contained. In the practical enterprise this nozzle worked after 2700 m still zufdedensteUend; at this time conditions were unchanged in the hottest section augenschelnllch. B e i s p i e 1 6: By presses of a fine-divided mixture from 86 Gew. - % zircon silicate and 14 Gew. - % copper with 1500°C and 280 kp: cm2 pressure was manufactured a nozzle. This nozzle was submerged two hours long in 1390°C hot cast iron with 1390°C, without an attack had to be recognized. The material was deterred after Abkäihlung on a temperature of 800°C in water and remained intact thereby which proved good ruggedness against thermal shock.