MXPA98002135A - Tool for tools configured - Google Patents

Abstract

The present invention relates to the steel obtained by means of the agglomerated powder metallurgical, previously alloyed, of high purity and density. According to the invention, the steel has the following composition by weight: Manganese < 1%, Silicon < 1%, Chrome 4.50-6-45%, Molybdenum 4-6%, Vanadium 6.10-6-50, Tungsten 18.20-18.70, Sulfur < = 0.20%, Phosphorous < = 0.030%, Oxygen < = 100 ppm, Cobalt 5-7%, Nitrogen 0.050-0.080%, Aluminum < .0020%, Carbon 1.80-1.95%. Since the complement is iron in addition to the impurities that are characteristic in the production of steel, the steel has for the most part, a dispersion of vanadium carbides of the type

Description

STEEL FOR CONFIGURATOR TOOLS In the aviation industry, ammunition and related industries, the materials that are made of steel have a great mechanical resistance, obviously it is essential to have a steel of fast cutting, extremely hard, through the metallurgy of the powders, which poses high tenacity , therefore offers an extremely high level of resistance of positive cutting edges. The object of the present invention is to provide fast cutting steel produced initially from the metallurgical of the powders, this steel turns out to be extremely hard with a "C" scale of Rockwell hardness of between 68 and 70 Ro. This steel, which is obtained from the agglomerated powder with a previous alloy, is characterized in that the alloy has the following composition: Percentages of heavy value: Preferred range Wide range Manganese 0.20-0.40 < 1% Silicon 0.20-0.40 < 1% Chromium 4.50-5 4.50-6.45% Molybdenum 4.50-5 4-6% Vanadium 6.10-6.50 6.10-6.50 Tungsten 18.20-18.70 18.20-18.70 Sulfur < 0.015% < 0.020% Phosphorous < 0.020% < 0.030% Oxygen < 100 ppm < 100 ppm Cobalt 5.40-6.20% 5-7% Nitrogen 0.050-0.080% 0.050-0.080% Aluminum < .015% < .020% Carbon 1.83-1.90% 1.80-1.95% Because the supplement is iron in addition to the impurities characteristic of metal production, the steel has a dispersion composed mainly of MC-type vanadium carbides. The steel of the present invention possesses a remarkable tension, due mainly to a distribution of the primary carbides associated with the hardness at extremely good elevated temperatures. In addition to the hardness, hardness at high temperatures, wear resistance and exceptional stress, the family of steels of the present invention can be particularly adapted to the forming tools: ability to work, hardness and solubility. The carbon content limited to 1.95 'is significant: beyond this value, the matrix could become fragile. The low oxygen content, less than 100 ppm, prevents the oxygen from forming an oxide film on the surface, which could create a wide network of oxides in the steel followed by isostatic compaction. This oxygen content, combined with the lower 800 ppm nitrogen content, guarantees extremely clean products. The stoichiometric ratio to form the vanadium carbide (of the cubic MC type with the centered face) is 1 vanadium per 0.020% carbon. The carbon content of the steel is balanced with its content of vanadium, chromium, molybdenum and tungsten, to provide a sufficient amount of carbon and thus allow treatment by heat and thus obtain a hardness of 66 Hrc. According to the invention, the steel for the shaping tools has a combination of different qualities: high temperature resistance characterized by the Mathon cutting capacity test, the tension that had not been obtained until now. The voltage is determined by the measurement according to the Charpy test referred to in ASTM-23-9 and 23-93. A reference piece of 10 x 10 x 55 mm was treated at a temperature of 160 ° C, stopped in oil or with an isothermal stop at a temperature of 560 ° C, followed by an annealing of one hour at 560 ° C. Then, it presents a tension greater than 40 days / cm2. The cutting capacity was characterized or determined by the MATHON test (defined in the AFNOR standard A-03-654)

Claims (2)

1. The steel obtained by the metallurgical powders and formed from a powder, with a previous, dense and agglomerated alloy, characterized in that the steel has the following composition by weight: Percentages of the heavy value: Manganese < 1% Silicon < 1% Chromium 4.50-6.45% Molybdenum 4-6% Vanadium 6.10-6.50 Tungsten 18.20-18.70 Sulfur < 0.020% Phosphorous < 0.030% Oxygen < 100 ppm Cobalt 5-7% Nitrogen 0.050-0.080% Aluminum < .0020% Carbon 1.80-1.95% Since the complement is iron in addition to the impurities characteristic of steel production, the steel has a dispersion composed mainly of vanadium carbides of the MC type. The steel according to claim 1, characterized in that the alloy has the following general composition: Manganese 0.20-0.40 Silicon 0.20-0.40 Chromium 4.50-5 Molybdenum 4.50-5 Vanadium 6.10-6.50 Tungsten 18.20-18.70 Sulfur < 0.015% Phosphorus = 0.020% Oxygen < 100 ppm Cobalt 5.40-6.20% Nitrogen 0.050-0.080% Aluminum < .015% Carbon 1.83-1.90%