Lengthscale effects in optical strain measurement for fracture characterization in simple shear

Khameneh, F.; Abedini, Armin; Butcher, Cliff

doi:10.1007/s10704-021-00598-9

Cited by 10 publications

(5 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Consequently, the frame rate of 5 Hz is used in all analyses for consistency and obtaining the requirements. A detailed analysis of the VSG and DIC parameters on shear testing is provided by Khameneh et al [39]. A strain filter of 7, step size of 2 pixels, and subset size of 29 pixels result in a VSG value of 0.625 mm.…”

Section: Methodsmentioning

confidence: 99%

“…It is emphasized that the DP1180 steel used in the study is commercially available. Additional information regarding the characterization of the same lot of DP1180, encompassing its shear behavior, formability, and constitutive properties, can be found in the following works: Khameneh et al [39], Fast-Irvine et al [38], Butcher et al [40], Noder et al [9], and Abedini et al [37,41]. Furthermore, an extensive volume of test data for the same lot of DP1180 steel is publicly available as part of the Numisheet 2022 fracture benchmark on non-linear strain paths [42].…”

Section: Stressmentioning

confidence: 99%

“…The preliminary fracture locus of the DP1180 was calibrated using four experimental points in shear, uniaxial, plane strain, and biaxial loading conditions. The fracture data was adapted from recent studies by the authors on the same lot of DP1180 as part of the Numisheet 2022 [42] non-linear fracture benchmark [39]. The experimental fracture strains and stress triaxialities for plane stress loading conditions are provided in Table 4.…”

Section: Calibration Of the Fracture Locus Of Dp1180mentioning

confidence: 99%

“…The finite element evaluations of both geometries are provided in Section 3.2. The second geometry considered for combined shear and tensile loading is the modified mini-shear geometry of Peirs et al [52], which has previously been investigated for the same lot of DP1180 by Khameneh et al [39], with fracture appearing to initiate in the gauge region and not at the edges. Therefore, the eccentricities in the geometry of Peirs et al [53] can be varied to determine if a combined state of uniaxial tension and simple shear can be obtained.…”

Section: Geometry Selectionmentioning

confidence: 99%

“…Stress triaxialities and equivalent fracture strains of DP1180 in four loading conditions described in Khameneh et al[39]. The values in the parentheses are the standard deviation of the repeated tests.…”

mentioning

confidence: 99%

See 4 more Smart Citations

Experimental and Numerical Fracture Characterization of DP1180 Steel in Combined Simple Shear and Uniaxial Tension

Khameneh

Abedini

Butcher

2023

Metals

Self Cite

View full text Add to dashboard Cite

Current tests for plane stress characterization of fracture in automotive sheet metals include simple shear, uniaxial, plane strain, and biaxial tension, but there is a significant gap between shear and uniaxial tension. Presently, it remains uncertain whether the fracture strain experiences a reduction between simple shear and uniaxial tension or undergoes an exponential increase as the triaxiality decreases. Fracture in combined simple shear and tension is complicated by premature edge cracking in tension along with a strong sensitivity of fracture strain to the measurement lengthscale. To address these issues, several existing simple shear geometries were modified and evaluated, with a focus on obtaining approximately linear strain paths corresponding to combined uniaxial tension and simple shear suitable for experimental fracture characterization using digital image correlation (DIC). An experimental and numerical investigation was conducted using two planar geometries that do not require through-thickness machining and can be easily tested on a universal test frame. Finite-element analysis was used to investigate the influence of the notch eccentricity on the stress state and predicted fracture location. The most promising geometry in each coupon type was then selected and tested for a dual-phase advanced high-strength steel, DP1180. The performance of the two planar geometries was evaluated based on the linearity of strain and stress state, along with the location of fracture initiation. The best geometry was then used to evaluate and recalibrate the modified Mohr-Coulomb (MMC) fracture locus with data in combined shear and tension. The initial MMC calibration using four fracture tests that suppressed necking provided an accurate estimate for the fracture strain in combined uniaxial tension and simple shear. The MMC model correctly predicted a valley in the fracture strain between these two loading conditions.

show abstract

Section: Methodsmentioning

confidence: 99%