The Boeing Company

Ultramet Incorporated

Jerry W Brockmeyer

Robert H Tuffias

Clifford C Bampton

Brian E Williams

Andrew J Sherman

Eric J Krieg

Andreas C Straub

Gregory Peters

A rhenium alloy is provided having from about 50 atomic % to 99 atomic % rhenium and a refractory compound particulates that are present in the alloy in an amount up to about 10 atomic %. The refractory compound comprises a nano-scale dispersion that is incorporated into the conventional rhenium structure. The nano-scale dispersion acts as grain boundary pins that result in a relatively fine grained, equiaxed structure that improves the mechanical properties of the alloy and helps to minimize the growth of large grains during operations at high temperatures. As a result, the amount of the rhenium used in high temperature applications may be reduced without sacrificing its high temperature and mechanical properties. Cryomilling in the presence of nitrogen may be used to prepare the rhenium alloy having a stable fine grain structure at high temperatures.

Rhenium composite alloys and a method of preparing same

A composite rigid foam structure that has a skin or coating on at least one of its surfaces. The skin is formed in situ by thermal spray techniques. The skin is bonded substantially throughout the surface of the porous substrate to the peripheries of the pores. The skin on the average does not penetrate the surface of the substrate by more than the depth of about 2 to 5 pores. Thus, thermal spraying the skin onto the rigid foam produces a composite that is tightly and uniformly bonded together without unduly increasing the weight of the composite structure. Both thermal conductivity and bonding are excellent.

Composite foam structures

A muzzle flash and blast suppressor comprising a body of reticulated refractory foam generally surrounding the projectile path adjacent the muzzle of a device. One side of the body of foam is exposed to the pressure within the projectile path just behind the projectile, and the other side is exposed to the unconfined ambient pressure. The foam is required to be possessed of sufficient structural strength to permit its exterior side to be exposed without confinement to the ambient environment. Hot exhaust gasses flowing laterally of the projectile path pass through the body from the high to the low pressure side. In such passage the gasses are cooled by expansion and by contact with the interstices of the body. Debris is filtered out and the pressure is substantially reduced. Typically, the refractory foam has from approximately 30 to 100 pores per inch and is from approximately 90 to 50 percent void volume.

Flash suppressor

A method for fabricating a fiber-reinforced ceramic matrix composite (FRCMC) part includes the steps of forming a blank from FRCMC material such that the blank has a dimension approximating a desired finished dimension for the part measuring the dimension of the blank in an unloaded condition, applying a load to the blank and then removing the load so as to cause permanent strain of the blank, measuring the dimension of the blank after the load has been applied and then removed, and comparing the measured dimension after loading to the previously measured dimension. In a preferred embodiment of the invention, if the dimension after loading differs from the dimension previously measured, the loading and measuring steps are repeated. After each loading cycle, the blank is measured and the measured dimension is compared to that previously measured after the prior loading cycle. The loading cycles are continued until the measured dimension differs from the previously measured dimension by less than a predetermined amount such that the blank has achieved dimensional stability with loading. After dimensional stability has been achieved, the final machining of the blank is performed to conform the dimension to the desired dimension.

Growing community of inventors

Santa Clarita, CA, United States of America

Jerry W Brockmeyer