A calibration method for brittle fracture assessment parameters for pressure vessel materials based on the Beremin model includes selecting at least two types of specimens of different constraints, and calculating the fracture toughness values K.sub.0 corresponding to 63.2% failure probability for each type of specimens at a same calibration temperature by using the respective fracture toughness data. The method proceeds by obtaining the stress-strain curve of the material at the calibration temperature, generating finite element models for each type of specimens, and calculating the maximum principal stress and element volume of every element at K=K.sub.0 in each model. A series of values of m are assumed to compute a group of σ.sub.u values for each type of specimens, and then m˜σ.sub.u curves are plotted for each type of specimens. Brittle fracture assessment parameters are then determined for the material according to the coordinates of the intersection of the m˜σ.sub.u curves.

A calibration method for brittle fracture assessment parameters for pressure vessel materials based on the Beremin model includes selecting at least two types of specimens of different constraints, and calculating the fracture toughness values K.sub.0 corresponding to 63.2% failure probability for each type of specimens at a same calibration temperature by using the respective fracture toughness data. The method proceeds by obtaining the stress-strain curve of the material at the calibration temperature, generating finite element models for each type of specimens, and calculating the maximum principal stress and element volume of every element at K=K.sub.0 in each model. A series of values of m are assumed to compute a group of σ.sub.u values for each type of specimens, and then m˜σ.sub.u curves are plotted for each type of specimens. Brittle fracture assessment parameters are then determined for the material according to the coordinates of the intersection of the m˜σ.sub.u curves.

A manufacturing method that includes fabricating a component using an additive manufacturing process, and fabricating a coupon using the additive manufacturing process. The coupon includes a main portion and a grip portion. Fabrication of the coupon includes fabricating the main portion concurrently with the fabrication of the component, fabricating the grip portion dissociatedly from the fabrication of the component, and coupling a first end of the main portion with the grip portion to form the coupon.

A manufacturing method that includes fabricating a component using an additive manufacturing process, and fabricating a coupon using the additive manufacturing process. The coupon includes a main portion and a grip portion. Fabrication of the coupon includes fabricating the main portion concurrently with the fabrication of the component, fabricating the grip portion dissociatedly from the fabrication of the component, and coupling a first end of the main portion with the grip portion to form the coupon.

The present disclosure describes systems and methods to correct for perspective calibration variations of a variable thickness specimen with a single camera extensometer in a video extensometer system. In some examples, the systems and methods compensate for a change between a reference characteristic, such as a calibration plane, and an actual physical characteristic, such as a testing plane associated with a surface of a test specimen, during a testing operation. In some examples, a correction value is applied to an output (e.g., measured dimensions of the imaged test specimen) to compensate for the difference between the reference characteristic and the physical characteristic.

The present disclosure describes systems and methods to correct for perspective calibration variations of a variable thickness specimen with a single camera extensometer in a video extensometer system. In some examples, the systems and methods compensate for a change between a reference characteristic, such as a calibration plane, and an actual physical characteristic, such as a testing plane associated with a surface of a test specimen, during a testing operation. In some examples, a correction value is applied to an output (e.g., measured dimensions of the imaged test specimen) to compensate for the difference between the reference characteristic and the physical characteristic.

An error compensation system and method may include applying a mechanical load to a reference sample to obtain a load measurement signal from the load sensor and a displacement measurement signal from the displacement sensor, calculating a transfer function to create a load filter and a displacement filter to be applied to the load measurement signal and the displacement measurement signal, respectively, applying the load filter to the load measurement signal to calculate a load compensation value, and applying the displacement filter to the displacement measurement signal to calculate a displacement compensation value, and determining the compensated value by comparing the load compensation value with the displacement compensation value, wherein the compensated value is determined prior to testing a specimen so that the compensated value is used to automatically correct a measured deflection of the specimen to arrive at an actual specimen deflection.

An error compensation system and method may include applying a mechanical load to a reference sample to obtain a load measurement signal from the load sensor and a displacement measurement signal from the displacement sensor, calculating a transfer function to create a load filter and a displacement filter to be applied to the load measurement signal and the displacement measurement signal, respectively, applying the load filter to the load measurement signal to calculate a load compensation value, and applying the displacement filter to the displacement measurement signal to calculate a displacement compensation value, and determining the compensated value by comparing the load compensation value with the displacement compensation value, wherein the compensated value is determined prior to testing a specimen so that the compensated value is used to automatically correct a measured deflection of the specimen to arrive at an actual specimen deflection.

A calibration determination device includes: a free roll that conveys the bonding member; a load detection device that detects a load applied to a bearing of the free roll; a tension adjustment device that winds the bonding member to increase a tension applied to the bonding member and unwinds the bonding member to reduce the tension applied to the bonding member so as to adjust the tension applied to the bonding member; and a calibration determination unit that determines whether calibration of the load detection device is necessary. The tension adjustment device unwinds the bonding member to cause the bonding member not to be subjected to the tension, and the calibration determination unit determines whether the calibration of the load detection device is necessary based on the load detected by the load detection device with the bonding member not being subjected to the tension.

A calibration determination device includes: a free roll that conveys the bonding member; a load detection device that detects a load applied to a bearing of the free roll; a tension adjustment device that winds the bonding member to increase a tension applied to the bonding member and unwinds the bonding member to reduce the tension applied to the bonding member so as to adjust the tension applied to the bonding member; and a calibration determination unit that determines whether calibration of the load detection device is necessary. The tension adjustment device unwinds the bonding member to cause the bonding member not to be subjected to the tension, and the calibration determination unit determines whether the calibration of the load detection device is necessary based on the load detected by the load detection device with the bonding member not being subjected to the tension.