There is a method of making a tubular specimen with a predetermined wrinkle defect including providing a layup tool with a cavity forming member having a cavity which resembles a desired shape of the at least one wrinkle; orienting a composite material around the mandrel at a wrap angle to form a closed loop; positioning a wrinkle tool on the closed loop; and/or generating at least one wrinkle with a predetermined characteristic in a portion of the closed loop to form a tubular specimen. The predetermined characteristic is at least one of the following: wrinkle location, an outward wrinkle, an inward wrinkle, a wrinkle width, a wrinkle height, and a wrinkle length. In another aspect, there is a method of offset load testing a tubular composite specimen. In a third aspect, there is a method of determining allowable defects for a composite component.

A notch treatment method for flaw simulation including providing the specimen with the notch, the notch having a re-melt material layer; isolating the notch; and selectively etching the notch to provide an etched surface of the notch; wherein at least a portion of the re-melt material layer has been removed from the notch. In one aspect, there is provided a notch treatment method for flaw simulation including providing the specimen with the notch, the notch having a re-melt material layer, the specimen includes steel or an alloy thereof; isolating the notch; and selectively etching the notch with a first etching solution and a second etching solution to provide an etched surface on the notch; wherein at least a portion of the re-melt material layer has been removed from the notch.

A monolithic precursor test coupon includes a first grip portion, a second grip portion, and an intermediate portion, interconnecting the first grip portion and the second grip portion. The monolithic precursor test coupon also includes runners, directly interconnecting the first grip portion and the second grip portion and not directly connected to the intermediate portion. The first grip portion, the second grip portion, the intermediate portion, and the runners are composed of a substance that comprises metal powder and that is in a green state.

A fixed value residual stress test block, comprising a main body (1) and two welded blocks (2); the main body (1) and the welded blocks (2) are all rectangular metal blocks; the welded blocks (2) are welded onto the two opposite side surfaces of the main body (1); the main body (1) is deformed under the upper and lower pressures and generates residual stress. The fixed value residual stress test block has a simple structure.

The present invention relates to a method for evaluating the properties of a plastic resin molded product, more specifically to a novel method for evaluating the properties of a plastic resin molded product that can exactly derive impact resistance of practically prepared molded products, using the property measurement values by the existing ASTM.

A symmetrical, flat laminate structure used to minimize variables in a test structure to experimentally gauge white bump sensitivity to CTE mismatch is disclosed. The test structure includes a flat laminate structure. The method of using the test structure includes isolating a cause of a multivariable chip join problem that is adversely impacted by warpage and quantifying a contribution of the warpage, itself, in a formation of the multivariable chip join problem.

A method of testing a material sample of a type used in a wall of a structure in a standard test for in-plane fracture toughness evaluation. The method comprises obtaining a sample having a lateral length no larger than a thickness of the wall of the structure, shaping the sample to have (a) a bottom surface, (b) a profiled top surface having a central notch, (c) a first coupling feature on a first side of the central notch, and (d) a second coupling feature on a second side of the central notch, assembling a test specimen which increases the width of the sample beyond the lateral width by coupling a first lateral extension to the first coupling feature and a second lateral extension to the second coupling feature, and applying a standard fracture toughness test to the so-assembled test specimen and sample to evaluate the fracture toughness of the sample.

A method for measuring the dynamic stress field evolution law of a complex heterogeneous structure, comprising: preparing a transparent photosensitive resin model of a complex heterogeneous structure by means of three-dimensional (3D) printing technology to serve as a test piece (S101); placing the test piece in a light path of a circularly polarized light dark field, performing continuous stress loading on the test piece, and recording images (S102); acquiring a plurality of continuously changing full-field stress fringe grayscale images according to videos generated by the image recording (S103); then acquiring grayscale value change sequences of pixel points at each position in the images (S104); and finally, calculating full-field fringe orders under continuous loading conditions according to the relation between the grayscale values and the fringe orders so as to calculate full-field stress values under the continuous loading conditions (S105). Thus, it is possible to extract and quantify the global dynamic stress field evolution law of a complex heterogeneous structure subjected to high exterior load under fixed light field conditions.

A testing method of thermal barrier coating (TBC) is for evaluating presence or absence of damage to TBC formed on a bending part on which compression stress acts. The method includes a test piece that includes a pair of arm parts, a bending part arranged between the pair of arm parts, and a TBC layer on a bending surface of the bending part; attaching the test piece to a compression testing device after preparing the test piece; and applying compression stress to the test piece in a direction for bringing the pair of arm parts close together after attaching the test piece with the compression testing device. The pair of arm parts are arranged so as to separate from each other from base end portions toward front end portions of the arm parts. The bending part is arranged between the base end portions.

A foam backed composite panel having two or more layers of materials adhesively bonded to each other. The panel is comprised of a cementitious material as a face layer and/or an optional core layer backed by polyurethane foam bonded to the face or core layer. The polyurethane foam bonds the panel to a supporting frame. The foam backed panel has increased impact and fire resistance.