Abstract: Processes and apparatus for batch annealing work pieces in a hydrogen atmosphere use pressure swing sorption to recover hydrogen from the annealing exhaust. In preferred embodiments, hydrogen for the batch annealing is generated by reforming and the recovery of hydrogen is integrated with the reforming operation.
Abstract: A hot object is quenched after heat treatment. A hot gas stream having at least 20% by volume of hydrogen is taken from for example a carburising chamber of a furnace. The gas is cooled by passage through a heat exchanger, and is compressed in a compressor. The compressor has an aftercooler (not shown) to remove heat of compression from the gas. The cooled, compressed gas flows through nozzles into a quenching chamber. The gas leaves the nozzles at a velocity of at least 50 m/s and impinges upon the hot metal object so as to effect its quenching.
Abstract: A method for quenching metallic workpieces in a furnace space, includes subjecting a metallic workpiece to a heat treatment process in an evacuated furnace space. Before a quenching gas or mixture is passed into the furnace space, hydrogen is supplied to the still evacuated furnace space. The amount of hydrogen supplied to the furnace space is limited so that, depending on (1) the quenching pressure, (2) the gas temperature at the end of the quenching process, and (3) the composition of the quenching gas or mixture, a hydrogen concentration below the explosive limit is reached in the quenching gas or mixture. The quenching gas or mixture contains an inert gas or a mixture of inert gases, such as nitrogen, argon and/or helium.
Abstract: A protective atmosphere for the heat-treatment of metals is obtained by heating a reactor containing a Nickel-based catalyst to a temperature of between 1000.degree. C. and 1200.degree. C., feeding to the reactor a flow of nitrogen having an oxygen content of between 0.1% and 9% and a flow of hydrocarbons that is substantially stoichiometric to the content of oxygen in the flow of nitrogen to obtain CO and H.sub.2, and sending the gas from the catalytic reactor (2) to a heat-treatment furnace (1). The flow of hydrocarbons is interrupted periodically or by command while maintaining the flow of nitrogen, and is resumed after a preset or calculated time.
Abstract: This invention relates to a process for heat treating light-metal castings, particularly cylinder heads for piston engines, in which, after solidifying and removing the castings from the mold, they are solution treated with the residual casting heat at approximately 530.degree. C., are quenched, aged at approximately 170 to 210.degree. C. and are then cooled to room temperature. The castings are quenched individually with a mist-type fine mixture of air and water, which is nozzle sprayed on all sides by forced convection flow only to approximately 130 to 160.degree. C., and are charged at this temperature, while utilizing the residual heat, into an aging furnace. The evaporation heat of the water is utilized as latent cooling heat. The forming water vapor, carried away by the workpieces, is condensed and the condensed water is guided back to moisten the air/water mixture.
Abstract: The present invention presents a method and an apparatus for heat treating a metallic material by performing hydrogen absorption in or desorption from the metallic material. The method includes the steps of recovering the hydrogen gas released from a desorption step and recycling it to a hydrogen absorbing step. Hydrogen recovering can be performed either in a device containing a hydrogen absorbing alloy or in a second heat treating furnace containing the metallic material. Various controlling devices are used to regulate the process of heat treating and recovering of hydrogen gas.
Abstract: The surfaces of a metal or alloy component are scrubbed by a high-velocity stream of inert gas at temperatures which facilitate removal of contaminants. Simultaneous with scrubbing, the impurities are captured in a separated loop of one or more "getter" filters operating at optimized temperatures. The scrubbing and "getting" functions are followed by a rapid elevation of the temperature of the component by heating the inert gas, now essentially free of contaminants which would otherwise react with the component surface at the elevated temperatures. Thereafter, a specific protective layer-forming agent is introduced into the inert gas stream at an ideal temperature, which agent will react predictably with the component being treated to form a predetermined protective coating on its surface.