Abstract: A torque limiting includes first and second rotational plates, first and second springs, and a slip device. The first rotational plate is coupled to a torque input device. The second rotational plate is coupled to a drive shaft, and is configured to be movable along an axial direction thereof. The first spring has a first free length, and exerts a first spring force against the second rotational plate toward the first rotational plate. The second spring has a second free length, smaller than the first free length, and selectively exerts a second spring force against the second rotational plate toward the first rotational plate. The slip device, disposed at least partially within or between the first and second rotational plates, causes relative motion between the first and second rotational plates when torque overcomes the combined first and second spring forces exerted against the second rotational plate.

Abstract: A hot gas valve disc for a divert and attitude control disc switching element used in a propelled craft. The hot gas valve disc comprises a first layer comprising a first metal material having a first grain size and a first grain orientation, and at least one additional layer comprising a second metal material having a second grain size that differs from the first grain size, or a second grain orientation that differs from the first grain orientation. A method of manufacturing the hot gas valve disc comprises the steps of fabricating a first metal layer using a solid-free-form fabrication process, the first metal layer having a set of grain characteristics comprising grain size and grain structure, followed by heating the first layer and thereby changing at least one of the grain characteristics.

Abstract: A torque limiting includes first and second rotational plates, first and second springs, and a slip device. The first rotational plate is coupled to a torque input device. The second rotational plate is coupled to a drive shaft, and is configured to be movable along an axial direction thereof. The first spring has a first free length, and exerts a first spring force against the second rotational plate toward the first rotational plate. The second spring has a second free length, smaller than the first free length, and selectively exerts a second spring force against the second rotational plate toward the first rotational plate. The slip device, disposed at least partially within or between the first and second rotational plates, causes relative motion between the first and second rotational plates when torque overcomes the combined first and second spring forces exerted against the second rotational plate.

Abstract: A non-lubricated component configured to have friction contact with another component and machine systems including the component are provided. In an embodiment, by way of example only, the non-lubricated component includes an outer surface consisting essentially of rhenium having a purity of at least 99%, by weight. The outer surface of the non-lubricated component is capable of being substantially wear- and gall-resistant when contacted by another component at a stress of above 50 ksi.

Abstract: A method is provided for manufacturing a magnetic steel component. An electroless nickel plating is formed on a substrate that includes magnetic steel. A thermal cycle is thereafter performed at a temperature that is sufficiently high to sinter the electroless nickel plating and thereby form a densified plating on the substrate. According to one embodiment, the thermal cycle includes a solid state diffusion sintering process wherein the substrate and the densified plating are heated to a temperature of at least about 1300° F. (about 704° C.) but.below the melting temperature of the electroless nickel plating. According to another embodiment, the thermal cycle includes a transient liquid phase sintering process wherein the substrate and the densified plating are heated at least to the melting temperature of the electroless plating.

Abstract: An actuator that at least inhibits the deleterious effects of corrosive fluids, such as salt-laden air, does not rely on relatively expensive materials. At least a portion of the actuator housing is sealed from the surrounding salt-laden air, and is in fluid communication with an air reservoir that includes a supply of relatively salt-free, or substantially salt-free, air. The actuator is configured to exchange air between the air reservoir and the actuator housing, thereby at least substantially inhibiting the ingress of salt-laden air into much of the actuator.

Abstract: The present invention provides a method for preparing a rhenium-tantalum alloy with improved strength and ductility characteristics. The method includes mixing powders of rhenium and tantalum with a weight ration of approximately 97% rhenium to approximately 3% tantalum. The powdered blend is then compressed to a green state. The green compress of rhenium and tantalum is then sintered such that tantalum goes into solid solution with rhenium. The sintered material is then cold rolled. The cold rolling disperses oxides away from concentrations in the alloy grain boundaries. If desired, the alloy may then be annealed. The result is a rhenium-tantalum alloy that displays improved high temperature strength and ductility over pure rhenium materials. The present alloy is particularly suited to fabrication of rocketry components such as valve bodies, poppets, seats, and nozzles.

Abstract: A valve is disclosed for use in hot gas applications such as in rocket or missile engine systems or the like. The valve is designed to withstand the extreme temperatures encountered in the gas exhaust from rocket propellants. The valve seat of the valve is constructed of fibrous monolith ceramic. This material does not degrade significantly when rocket exhaust, such as resulting when ammonium perchlorate propellant is burned, is ported through the valve. The valve generally includes a valve body, a valve seat, through which gases may pass, and a poppet which opens and closes the valve by pressing against and moving away from the valve seat.