A bolted attachment having opposite threaded sections between which a shank is provided having at least two shank sections with different diameter located at a length from the threaded section of at least three times the difference between a diameter of a threaded section and a minimum diameter of the shank. At least one conical transition is formed between two adjacent shank sections where the ratio of its length to a difference between a diameter at one end of the transition and a diameter at the opposite end of the transition is of at least 0.85.

A structure configured to rotate about an axis may include a fastener opening defined in a surface of the structure. The fastener opening may extend through the surface and include a circular portion, a first slot portion, and a second slot portion. The circular portion may include a first radius of curvature. The first slot portion may extend from the circular portion circumferentially relative to the axis. The second slot portion may also extend from the circular portion circumferentially relative to the axis.

Steel for a high-strength bolt contains: from 0.50 mass % to 0.65 mass % carbon, from 1.5 mass % to 2.5 mass % silicon, 1.0 mass % or more chromium, 0.4 mass % or less manganese, greater than 1.5 mass % molybdenum, 0.03 mass % or less phosphorus and sulfur combined, and balance iron and inevitable impurities.

A high-strength bolt is formed using steel for a high-strength bolt that contains: from 0.50 mass % to 0.65 mass % carbon, from 1.5 mass % to 2.5 mass % silicon, 1.0 mass % or more chromium, 0.4 mass % or less manganese, greater than 1.5 mass % molybdenum, 0.03 mass % or less phosphorus and sulfur combined, and balance iron and inevitable impurities.

Steel for a high-strength bolt contains: from 0.50 mass % to 0.65 mass % carbon, from 1.5 mass % to 2.5 mass % silicon, 1.0 mass % or more chromium, 0.4 mass % or less manganese, greater than 1.5 mass % molybdenum, 0.03 mass % or less phosphorus and sulfur combined, and balance iron and inevitable impurities.

A high-strength bolt is formed using steel for a high-strength bolt that contains: from 0.50 mass % to 0.65 mass % carbon, from 1.5 mass % to 2.5 mass % silicon, 1.0 mass % or more chromium, 0.4 mass % or less manganese, greater than 1.5 mass % molybdenum, 0.03 mass % or less phosphorus and sulfur combined, and balance iron and inevitable impurities.

A barrel nut with features for reducing tensile stresses under heavy load within the barrel nut has a partial-cylindrical body having a first planar end surface and a second planar end surface. A threaded bore extends through the partial-cylindrical body with a central axis substantially parallel to the first planar end surface and the second planar end surface. At least one groove is formed in each of the first planar end surface and the second planar end surface, the groove having a rounded surface extending at least a part of a distance between a curved upper surface of the partial-cylindrical body to a bottom surface thereof in a direction substantially parallel to the central axis of the threaded bore.

A barrel nut with features for reducing tensile stresses under heavy load within the barrel nut has a partial-cylindrical body having a first planar end surface and a second planar end surface. A threaded bore extends through the partial-cylindrical body with a central axis substantially parallel to the first planar end surface and the second planar end surface. At least one groove is formed in each of the first planar end surface and the second planar end surface, the groove having a rounded surface extending at least a part of a distance between a curved upper surface of the partial-cylindrical body to a bottom surface thereof in a direction substantially parallel to the central axis of the threaded bore.

A structural fuse is disclosed and configured to shear upon an application of a predetermined load and includes a plurality of elongate reinforcing elements in a metal matrix. The provision of a so-called metal matrix composite results in a fuse that is lighter in weight than a conventional metal pin and has improved fatigue properties and hence a longer operating life. The load (or range of loads) at which the fuse is arranged to shear can be engineered by careful arrangement of the orientation of the reinforcing elements, and by selecting the proportion of reinforcing elements in the matrix. Thus, a fuse having a narrower load range than hitherto achievable can be produced.

A thermally stabilized fastener system and method is disclosed. The disclosed system/method integrates a fastener (FAS) incorporating a faster retention head (FRH), fastener retention body (FRB), and fastener retention tip

(FRT) to couple a mechanical member stack (MMS) in a thermally stabilized fashion using a fastener retention receiver (FRR). The MMS includes a temperature compensating member (TCM), a first retention member (FRM), and an optional second retention member (SRM). The TCM is constructed using a tailored thermal expansion coefficient (TTC) that permits the TCM to compensate for the thermal expansion characteristics of the FAS, FRM, and SRM such that the force applied by the FRH and FRR portions of the FAS to the MMS is tailored to a specific temperature force profile (TFP) over changes in MMS/FAS temperature. The TCM may be selected with a TTC to achieve a uniform TFP over changes in MMS/FAS temperature.

A thermally stabilized fastener system and method is disclosed. The disclosed system/method integrates a fastener (FAS) incorporating a faster retention head (FRH), fastener retention body (FRB), and fastener retention tip

(FRT) to couple a mechanical member stack (MMS) in a thermally stabilized fashion using a fastener retention receiver (FRR). The MMS includes a temperature compensating member (TCM), a first retention member (FRM), and an optional second retention member (SRM). The TCM is constructed using a tailored thermal expansion coefficient (TTC) that permits the TCM to compensate for the thermal expansion characteristics of the FAS, FRM, and SRM such that the force applied by the FRH and FRR portions of the FAS to the MMS is tailored to a specific temperature force profile (TFP) over changes in MMS/FAS temperature. The TCM may be selected with a TTC to achieve a uniform TFP over changes in MMS/FAS temperature.

A thermally stabilized fastener system and method is disclosed. The disclosed system/method integrates a fastener (FAS) incorporating a faster retention head (FRH), fastener retention body (FRB), and fastener retention tip (FRT) to couple a mechanical member stack (MMS) in a thermally stabilized fashion using a fastener retention receiver (FRR). The MMS includes a temperature compensating member (TCM), a first retention member (FRM), and an optional second retention member (SRM). The TCM is constructed using a tailored thermal expansion coefficient (TTC) that permits the TCM to compensate for the thermal expansion characteristics of the FAS, FRM, and SRM such that the force applied by the FRH and FRR portions of the FAS to the MMS is tailored to a specific temperature force profile (TFP) over changes in MMS/FAS temperature. The TCM may be selected with a TTC to achieve a uniform TFP over changes in MMS/FAS temperature.