Forgings, Hardenable Steels and Corrosion-Resistant Steels, Heat-Treated, Finished-Part Properties, Short-Transverse Tensile Strength and Fracture Toughness

Due to the observed dependence of transverse-tensile strength, Y T, on test geometry and specimen size, there is no consensus regarding a test method that can uniquely measure Y T. This study reexamines the characterization of Y T by comparing results from established flexure tests with results from a new tensile test that exhibits consistent failure in the gage region. Additionally, the effects of surface preparation and direction of transverse fracture are investigated. Results show that Y T is inversely proportional to specimen volume and surface roughness and is insensitive to direction of transverse fracture. The relationship between specimen volume and Y T is adequately captured by Weibull strength-scaling theory, except at the tails of the Y T distributions. However, specimens exhibited microcracking prior to failure, which violates the “weak-link” assumption of the Weibull theory. These findings highlight the challenges of using deterministic Y T values in progressive damage analysis.

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Investigation of Interlaminar Defects and their Influence on Interlaminar Strength

Advanced Composites Letters ◽

10.1177/096369359600500404 ◽

1996 ◽

Vol 5 (4) ◽

pp. 096369359600500

Author(s):

J Ziao ◽

J Tao

Keyword(s):

Tensile Strength ◽

Large Scale ◽

Peel Strength ◽

Test Method ◽

Bending Test ◽

Four Point Bending ◽

Transverse Tensile ◽

Interlaminar Shear ◽

Transverse Tensile Strength ◽

Set Up

In this paper, we directed our attention to the interlaminar defects and their influence on the interlaminar strengths. With the aid of a S-570 scanning electron microscope, the morphology and distribution of interlaminar defects were inspected and documented. According to their shape, size and cause of formation, the defects were classified into five types: flakiness void, irregular shaped debond, local imperfectly cured resin, debond in two multi-directional plies, and inhomogeneous fibers and the large scale debond by these fibers. The cause of defects formation was discussed by analyzing the manufacturing process of composites. The influence of defects on the interlaminar strength and its mechanism was analyzed experimentally and theoretically. The results indicate that these defects, with different effects, decrease the interlaminar strength because they form interlaminar cracks, and the interlaminar shear strength is less affected than interlaminar tensile strength, which is measured according to GB4944 test method. To comprehend defects distribution effect, a four-point-bending test method was introduced to measure the interlaminar peel strength, and a discussion was made on the correlation between the interlaminar tensile strength, interlaminar peel strength and in-plane transverse tensile strength. Finally the concept of interlaminar defect coefficient, which can be used to characterize the defects, was set up and the formula to calculate it was proposed.

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Steel, Corrosion-Resistant, Investment Castings, 16Cr - 4.1Ni - 0.28Cb - 3.2Cu, Homogenization, Solution, and Precipitation Heat Treated (H900), 180 ksi (1241 MPa) Tensile Strength (17-4)

10.4271/ams5344g ◽

2019 ◽

Author(s):

Keyword(s):

Tensile Strength ◽

Steel Corrosion ◽

Corrosion Resistant ◽

Heat Treated ◽

Precipitation Heat

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