Abstract: The invention relates to a method for producing corrosion-resistant surfaces of nitrated or nitrocarburated steel components, the surfaces having roughness heights (Rz) of Rz?1.5 ?m. The method comprises the following steps: oxidation of the surfaces of the nitrated or nitrocarburated components in a first oxidation step; carrying out at least a second oxidation of the component surfaces in an immediately subsequent oxidation step; polishing the component surface in a final method step, directly after the final oxidation.

Abstract: A method for hardening the surfaces of work pieces made from stainless steel includes submerging the work pieces into a molten salt bath having the composition: potassium acetate 60-100 weight %; sodium acetate 0-100 weight %; metal salt 0-2 weight %, and are subjecting the work pieces to the molten salt bath for a period of 24 to 240 hours, during which the temperature of the molten salt bath is maintained less than 400° C.

Abstract: The invention relates to an explosive comprising 2,6,10-trinitro-s-heptazine and/or derivatives thereof as an active chemical compound.

Abstract: A process for hardening a work piece of stainless steel through diffusion of the elements carbon and/or nitrogen into the work piece surfaces. The work piece is submerged into a molten salt bath and subjected to the molten salt bath for a period ranging from 15 minutes to 240 hours at temperatures below 450° C. In addition to potassium chloride and lithium chloride, the molten salt bath contains an activator substance consisting of barium chloride, strontium chloride, magnesium chloride and/or calcium chloride, and a free or complex cyanide as carbon-donating substance.

Abstract: The invention relates to a method for producing corrosion-resistant surfaces of nitrated or nitrocarburated steel components, the surfaces having roughness heights (Rz) of Rz?1.5 ?m. The method comprises the following steps: oxidation of the surfaces of the nitrated or nitrocarburated components in a first oxidation step; carrying out at least a second oxidation of the component surfaces in an immediately subsequent oxidation step; polishing the component surface in a final method step, directly after the final oxidation.

Abstract: A method for hardening the surfaces of work pieces made from stainless steel includes submerging the work pieces into a molten salt bath having the composition: potassium acetate 60-100 weight %; sodium acetate 0-100 weight %; metal salt 0-2 weight %, and are subjecting the work pieces to the molten salt bath for a period of 24 to 240 hours, during which the temperature of the molten salt bath is maintained less than 400° C.

Abstract: A process for hardening a work piece of stainless steel through diffusion of the elements carbon and/or nitrogen into the work piece surfaces. The work piece is submerged into a molten salt bath and subjected to the molten salt bath for a period ranging from 15 minutes to 240 hours at temperatures below 450° C. In addition to potassium chloride and lithium chloride, the molten salt bath contains an activator substance consisting of barium chloride, strontium chloride, magnesium chloride and/or calcium chloride, and a free or complex cyanide as carbon-donating substance.

Abstract: Hardening protection compositions based on substances which form boron glass for partial carburization of metallic components, which contain magnesium-silicon compounds as an additive. These hardening protection compositions can be used very advantageously in processes for the partial carburization of metallic components and in particular are outstandingly suitable for vacuum carburization.

Abstract: A boronizing agent in the form of a paste for the production of boride layers on metallic workpieces. The boronizing agent contains boron-releasing substances, activating substances and the remainder of inert, refractory extenders together with water and optionally auxiliaries required for paste formulation. It contains as additives: (a) calcium carbonate and/or lithium carbonate; (b) at least one compound from the group of alkali metal and alkaline earth metal nitrites; (c) at least one compound from the group of water soluble alkali metal and alkaline earth metal borates.

Abstract: A boronizing agent in the form of a paste for the production of boride layers on metallic workpieces. The boronizing agent contains boron-releasing substances, activating substances and the remainder of inert, refractory extenders together with water and optionally auxiliaries required for paste formulation.

Abstract: Hardening protection compositions based on substances which form boron glass for partial carburization of metallic components, which contain magnesium-silicon compounds as an additive. These hardening protection compositions can be used very advantageously in processes for the partial carburization of metallic components and in particular are outstandingly suitable for vacuum carburization.

Abstract: A boriding agent for generating boride layers on metallic workpieces, containing boron-releasing substances, activating substances and, in the remainder, refractory, inert extender. The activating substance is a combination of 1 to 5 wt. % potassium tetrafluoroborate and 5 to 40 wt. % calcium fluoride, relative to the total quantity of the boriding agent. With this boriding agent it is possible for single-phase, Fe2B-containing boride layers to be generated on workpieces made of ferrous materials. The agent results in lower emissions of fluorine and fluoride.

Abstract: In order to shorten the waiting times until the equilibrium between cyanate and cyanide is established and to limit the use of substances and products containing cyanide for nitrocarburizing in salt melts, melts containing only cyanate and optionally carbonate are electrolyzed at a current density of 4 to 100 A/dm.sup.2 of electrode area to form an advantageous cyanide content of 1 to 5 wt. %.

Abstract: There is provided a crucible for containing salt baths for the boriding of steels which has a high service life made of a steel which consists of (or consists essentially of) 0.05-0.8% carbon, 0.8-2.5% silicon, 0.1-2.0% manganese, 0-1.5% aluminum, 6-30% chromium, 4-39% nickel and the balance iron.

Abstract: There is described a salt bath based on an alkali and/or alkaline earth metal halide with which there can be produced without the use of current adherent and wear resistant boride coatings on metallic workpieces. This bath contains gaseous boron monofluoride or a compound from which there is formed intermediately boron monofluoride. Advantageous there is used a salt bath containing 30-60% BaCl.sub.2, 10-25% NaCl, 1-20% boron oxide or borate, 10-30% NaF, and 1-15% B.sub.4 C.

Abstract: It is known to regenerate salt baths for nitriding parts of iron and steel with polymers of organic materials, which polymers, however, could not be used in carburizing salt baths since with them there only are formed slight amounts of carburizing active cyanide, the baths foam, and carbon residues are formed. An excellent regeneration agent for carburizing salt baths is obtained by using polymeric organic compounds of the overall composition [C.sub.6 H.sub.x N.sub.y ].sub.z where x is 3 to 5, y is 5 to 8, and z is 10 to 10,000. These compounds are obtained by reacting formaldehyde with cyanamide and/or dicyandiamide and/or melamine and pyrolytically decomposing the reaction product at 300.degree. to 600.degree. C.

Abstract: For removing and dissolving sand mold residues from cast parts, particularly sand mold residues containing zirconium oxide and titanium oxide, there have previously been used mechanical and electrochemical processes in salt melts. However, these processes are very expensive, attack the surface of the cast pieces or fail to work with sand mold constituents which are difficult to dissolve. These disadvantages are avoided by inserting the cast parts having adhering sand mold residues into a melt of 55 to 97 weight % of alkali metal hydroxide and 3 to 45 weight % of one or more fluorides of an element of the first to third main group of the periodic system of elements and/or zinc at 400.degree. to 900.degree. C. Preferably the salt melt additionally contains a boron-oxygen and/or a boron-fluorine compound.

Abstract: Vanadium carbide layers are produced on iron and iron alloys having a content of at least 0.1 weight % carbon by treating the workpiece at 800.degree. to 1100.degree. C. in a salt bath which contains 1-30 weight % of vanadium or ferrovanadium powder. The salt bath consists of alkaline earth and/or alkali metal halide.