A fastener for securing at least a first component and a second component together, the fastener comprising: a securing portion adapted to be secured to the first and/or the second component, and a guiding portion adapted to be guided by a manipulator or a tool in order to set the securing portion in the first and/or the second component, wherein the securing portion and the guiding portion form a one-piece element made of one unique aluminium alloy having a composition between 0.03 and 0.55 wt % Scandium.

A fastener for securing at least a first component and a second component together, the fastener comprising: a securing portion adapted to be secured to the first and/or the second component, and a guiding portion adapted to be guided by a manipulator or a tool in order to set the securing portion in the first and/or the second component, wherein the securing portion and the guiding portion form a one-piece element made of one unique aluminium alloy having a composition between 0.03 and 0.55 wt % Scandium.

The present invention discloses methods and systems for detecting the health status of a bolt which fastens a rotor blade of a wind turbine. Values of the axial stress/strain of the bolt and motion and orientation data are acquired in different aerial orientations. Values of the prestress/strain and load-stress/strain are obtained using the values of the axial stress/strain and the motion and orientation data. Values of the prestress/strain and load-stress/strain are compared with the reference values. The health status of the bolt, rotor blade, and the wind turbine system is determined based on the comparison results. The method is noninvasive and doesn't affect the function and performance of the bolt and the turbine system.

A fastening structure (105) includes a pair of fastening members (105A) joined to each other, which is coupled with a bolt. The fastening member (105) is made of steel. A surface other than joint surfaces (Sa) has a Rockwell hardness of 50 HRC or more. The joint surfaces (Sa) have a Rockwell hardness of 30 HRC or more and less than 50 HRC. The joint surfaces (Sa) have an arithmetic mean roughness (Ra) of 0.2 m or more and 0.5 m or less. Production cost is suppressed, and at the same time, bending fatigue strength is secured and secondary damage due to abrasion powder generated by fretting is prevented.

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 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.

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.

A modified meta-stable # titanium alloy that, apart from carbon content, corresponds to the composition range for standard Beta-C titanium alloy. The modified alloy comprises vanadium, chromium, molybdenum, zirconium, aluminium, with maxima for oxygen, iron, nitrogen, hydrogen, yttrium, and other elements (apart from carbon and titanium), with a balance (apart from carbon) of titanium. The modified alloy has carbon present at a stable total carbon level sufficiently in excess of 0.05 wt. % achieving an improvement in the mechanical properties of UTS, DSS and fatigue strength in threaded regions, relative to standard Beta-C alloy with a specified carbon level below 0.05 wt. %, with a maximum carbon content controlled so as to preclude carbide formation having a detrimental effect on the level of fatigue strength.

A modified meta-stable # titanium alloy that, apart from carbon content, corresponds to the composition range for standard Beta-C titanium alloy. The modified alloy comprises vanadium, chromium, molybdenum, zirconium, aluminium, with maxima for oxygen, iron, nitrogen, hydrogen, yttrium, and other elements (apart from carbon and titanium), with a balance (apart from carbon) of titanium. The modified alloy has carbon present at a stable total carbon level sufficiently in excess of 0.05 wt. % achieving an improvement in the mechanical properties of UTS, DSS and fatigue strength in threaded regions, relative to standard Beta-C alloy with a specified carbon level below 0.05 wt. %, with a maximum carbon content controlled so as to preclude carbide formation having a detrimental effect on the level of fatigue strength.