Abstract:
A steel machine component, such as a bearing race, has a critical surface of generally circular configuration. Here the steel of the machine component exists in a state of compression to improve the physical characteristics of the surface. To this end, high speed steel is melted along the full circumference of the surface. Upon cooling to room temperature some of the austenite in the steel transforms into martensite. Tempering converts much of the remaining austenite into martensite, so that the machine component at the surface is almost entirely martensite. Martensite normally occupies a greater volume than austenite, but since the layer of martensite so formed is confined by the underlying core of the machine component, the layer exists in a state of compression. The high speed steel is melted with a laser beam that makes a trace over the full surface of the machine component. Where the underlying core is formed from high speed steel, the steel that is melted derives from the core itself, thus producing a glaze over the core. Where the underlying core is another type of steel, the high speed steel which is melted is supplied from an external source as a filler metal and becomes a cladding that lies over, yet is bonded to, the core.
Abstract:
A method of producing a metallic exhaust gas catalyst carrier body includes winding alternating layers of smooth and corrugated sheetmetal strips to form a blank and inserting the blank into a jacket tube, each winding of the blank being formed of a respective smooth and corrugated sheetmetal strip each having an individually predeterminable length; determining the length of each winding in accordance with the length necessary for filling a predetermined jacket tube cross section, fixing each winding beforehand to at least one side of the blank, so as to produce an approximately egg-shaped blank which is tightly wound on the one side and wound with varying looseness in the remaining region thereof; inserting the blank into the jacket tube in such a manner that the tightly wound side is located in a region of the jacket tube cross section in which a largest possible inscribed circle of the jacket tube cross section engages the jacket tube, and a device for carrying out the method, a carrier body formed by the method and device, and a blank forming part of the carrier body.
Abstract:
A selective laser sintering apparatus and method is disclosed, in which the laser power is controlled according to the scan velocity. The scanning system, which includes a pair of galvanometer-controlled mirrors for directing the aim of the laser beam, generates signals indicative of either the position or scan velocity of the aim of the beam, in either one or two directions. The signals are gated in the laser power control system so as to pass the signals only during those times at which the laser is to be turned on. A laser power control system receives the signals and, in the case of position signals, differentiates the signals to generate velocity signals. The velocity signals are used to derive a scan velocity, and the scan velocity is multiplied by the desired laser power at full scan velocity to produce a laser power control signal. By making the laser power dependent upon the scan velocity, a constant laser energy flux density is applied to powder at the target surface, even during acceleration and deceleration intervals at the beginning and end of a scan, respectively.
Abstract:
A method of producing a metallic exhaust gas catalyst carrier body includes winding alternating layer of smooth and corrugated sheetmetal strips to form a blank and inserting the blank into a jacket tube, each winding of the blank being formed of a respective smooth and corrugated sheetmetal strip each having an individually predeterminable length; determining the length of each winding in accordance with the length necessary for filling a predetermined jacket tube cross section, fixing each winding beforehand to at least one side of the blank, so as to produce an approximately egg-shaped blank which is tightly wound on the one side and wound with varying looseness in the remaining region thereof; inserting the blank into the jacket tube in such a manner that the tightly wound side is located in a region of the jacket tube cross section in which a largest possible inscribed circle of the jacket tube cross section engages the jacket tube, and a device for carrying out the method, a carrier body formed by the method and device, and a blank forming part of the carrier body.
Abstract:
The present invention relates to a blend of at least one boron source and at least one silicon source, wherein the blend comprises boron and silicon in a weight ratio boron to silicon within a range from about 5:100 to about 2:1, wherein silicon and boron are present in the blend in at least 25 wt%, and wherein the at least one boron source and the at least one silicon source are oxygen free except for inevitable amounts of contaminating oxygen, and wherein the blend is a mechanical blend of powders, and wherein particles in the powders have an average particle size less than 250 µm. The present invention relates further to a composition comprising the blend a substrate applied with the blend, a method for providing a brazed product, and uses.
Abstract:
The present invention relates to an intermediate product for joining and coating by brazing comprising a base metal and a blend of boron and silicon, said base metal having a solidus temperature above 1040 °C, and the intermediate product has at least partly a surface layer of the blend on the base metal, wherein the boron in the blend is selected from a boron source, and the silicon in the blend is selected from a silicon source, and wherein the blend comprises boron and silicon in a ratio of boron to silicon within a range from about 3:100 wt/wt to about 100:3 wt/wt. The present invention relates also to a stacked intermediate product, to an assembled intermediate product, to a method of brazing, to a brazed product, to a use of an intermediate product, to a pre-brazed product, to a blend and to paint.
Abstract:
The invention relates to a method of providing an aluminium conductor rail (1) used in electrolysis with a silver electric current supplier (6a, 6b, 6c) having a contact surface that conducts well electricity. In order for the conductor rail (1) and the electric current supplier (6a, 6b, 6c) thereof to be economical, easy and rapid to manufacture, a) the material selected for the conductor rail (1) is a aluminium-based alloy, b) the surface of the conductor rail (1) having an aluminium surface is heated and once the surface of the aluminium reaches a temperature exceeding the melting temperature of the solder, a zinc-based solder is arranged on top of it, the solder containing a substance with high affinity to oxygen and the solder being then spread in the molten state onto said surface, c) an aluminium oxide layer formed between the aluminium and the molten solder is broken by a mechanical treatment so that oxygen is released from the aluminium oxide layer, the oxygen reacting with the substance of high affinity to oxygen and forming together with said substance an oxide layer on the surface of the molten solder, and d) an electric current supplier (6a, 6b and 6c) is arranged on top of said solder, the solder is allowed to solidify and the electric current supplier to attach in place into the solidified solder. The invention also relates to a conductor rail (1).