The strength behavior of granulated silicon carbide at high strain rates and confining pressure

Abstract

The dynamic Mohr–Coulomb behavior of silicon carbide (SiC) was inferred from symmetric pressure/shear plate-impact experiments which entail planar impact of two SiC plates inclined at 15° to the impact direction. The transverse velocity of the free rear surface of the target plate was recorded using a laser Doppler velocimeter system, and the experiments were simulated using a postulated viscoplastic constitutive model that accounts for comminution and dilatancy. Model parameters were varied until the computed and measured velocity histories agreed. The results indicate that comminution occurred soon after loading, and thus the experiment measures the behavior of granulated material at shear strain rates of ≊105 s−1 and mean stress ranging from 1 to 9 GPa. A friction coefficient of 0.23 was obtained, which is about half the value for quasistatic compression of precomminuted ceramic reported in the literature. The simulation results were strongly affected by the values chosen for the friction coefficient and yield strength parameters; changes in the dilatancy, rate-sensitivity, and strain-hardening parameters had a lesser effect.

Modelling of failure mode transition in ballistic penetration with a continuum model describing microcracking and flow of pulverized media

“…Despite the fact that dilatancy is not taken into account, this model has been used to reproduce ID in the conÿguration proposed by Malaise et al [8]. Nevertheless, Malaise considered that friction between fragments in the comminuted zone is very small ( = 10 −3 ) which contradicts the measurement of in pressure-shear plate impact experiments performed by Klopp and Shockey [20] and Sairam and Clifton [21]. Moreover, the model is fully isotropic and therefore cannot capture damage anisotropy as observed in oblique impact.…”

Multiscale Modeling of Grain Boundary Segregation and Embrittlement in Tungsten for Mechanistic Design of Alloys for Coal Fired Plants

“…then modeled with hyperelastic constitutive behavior based on experimental evidence, 22,23 , and 24 . Digitalizing process of microstructural morphology are described in the figure below.…”

Computer Aided Multi-scale Design of SiC-Si3N4 Nanoceramic Composites for High-Temperature Structural Applications

“…(20) 1 ( Table 9 shows the results of the sequential approximate optimization under uncertainty algorithm. It details the current design (x n ) and candidate design (x n *) per iteration, showing that the optimum microstructure is given by the design x * = [10,19,9,7,3,8,8]. This design results in a more intermediate microstructure, compared to the results from cases A-D where designs did not show compromised microstructures.…”

“…We follow the second approach based on the work of [18] in our analyses. Each phase is modeled with hyperelastic constitutive behavior based on available experimental evidence, [19], [20], [21], and [22]. In the absence of the experimental information, the distribution of the crystalline orientation of the Si 3 N 4 and SiC phases is neglected.…”

“…The cohesive parameters are calculated using the experimental information on the elastic moduli and 0 Φ , [6], [20], [33], [34], [35], [36], [19], [21], [22].…”