On the mechanism of surface-parallel cracks formation under pulsed heat loads

Arakcheev, A. S.; Arakcheev, S.A.; Kandaurov, I. V.; Kasatov, A. A.; Kurkuchekov, V. V.; Lazareva, G. G.; Maksimova, A. G.; Mashukov, V. I.; Попов, В. А.; Trunev, Yu.A.; Vasilyev, Aleksey; Vyacheslavov, L. N.

doi:10.1016/j.nme.2019.100677

Cited by 4 publications

(3 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since the finite element model did not consider the local deformation generated by the formation of longitudinal cracks, the actual longitudinal tensile stress value was larger than the calculated value [27]. The transverse transformation of longitudinal cracks could be induced by longitudinal tensile stress and other factors, such as the direction of long grains parallel to the surface of the rolled sheet, and the inertia of motion during the formation of longitudinal cracks [27]. In addition, in the shaded zone of crack formation in figure 10(c), it can be noticed that the time when cracks started to form on the tungsten surface was later than those at about 110 µm depth, which meant that the cracks may preferentially sprout inside the material [35,54].…”

Section: Mechanical Simulation and Cracking Behaviormentioning

confidence: 92%

“…It is noteworthy that longitudinal tensile stresses were also generated in tungsten at a depth of about 110 µm during irradiation (red line in figure 10(d)). Since the finite element model did not consider the local deformation generated by the formation of longitudinal cracks, the actual longitudinal tensile stress value was larger than the calculated value [27]. The transverse transformation of longitudinal cracks could be induced by longitudinal tensile stress and other factors, such as the direction of long grains parallel to the surface of the rolled sheet, and the inertia of motion during the formation of longitudinal cracks [27].…”

Section: Mechanical Simulation and Cracking Behaviormentioning

confidence: 93%

“…Besides the ductile-to-brittle transition temperature (DBTT) of the material [22], the heat flux factor of the thermal shock irradiation [23], the base temperature of the material during irradiation [24,25] and the processing history of the material [26] are the key factors affecting macro-crack generation. Moreover, longitudinal macro-cracks extending perpendicular to the surface may undergo transverse transformation within the material [27,28].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Experimental and simulation studies on damage mechanisms of tungsten and molybdenum under compressed plasma flow irradiation

Zhang

et al. 2023

Nucl. Fusion

View full text Add to dashboard Cite

The failure mechanism of plasma-facing components (PFCs) under extreme plasma conditions relevant for fusion reactor were investigated. Here, edge-localized mode (ELM)-like transient thermal shock irradiation experiments were performed on tungsten and molybdenum using compressed plasma flow, and combined with thermal-mechanical analysis by means of finite element simulations to discuss the grain structure evolution, cracking behavior and variations of hardness. When ELM-like thermal shock irradiation was sufficient to melt tungsten and molybdenum, submicron-sized cellular sub-grain structure created on their surface due to the high temperature gradient of the molten layer under the effect of the Bénard-Marangoni instability. Rapid directional solidification from the bottom of the molten layer to the surface induced the formation of columnar grains dominated by <200> orientation. While the formation of cellular sub-grains increased hardness, the thermal effect of irradiation and the formation of columnar grains led to softening. The high thermal stress induced by the ELM-like thermal shock produced macro-cracks and micro-cracks on the surface of tungsten and only micro-cracks on the surface of molybdenum. Macro-cracks generated due to the intrinsic brittleness of tungsten. As a result of stress evolution, longitudinal macro-cracks extending perpendicular to the surface experienced transverse transformation within the material. Micro-cracks formed due to the embrittlement of the re-solidification zone, and their width increased with the melting depth. These results help to understand failure mechanisms in PFCs under extreme operation conditions which are valuable for developing future fusion reactors.

show abstract

Section: Mechanical Simulation and Cracking Behaviormentioning

confidence: 92%

Section: Mechanical Simulation and Cracking Behaviormentioning

confidence: 93%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Experimental and simulation studies on damage mechanisms of tungsten and molybdenum under compressed plasma flow irradiation

Zhang

et al. 2023

Nucl. Fusion

View full text Add to dashboard Cite

show abstract

Estimation of the change in the gas flow rate from the surface of a tungsten plate under pulsed heat load

Lazareva

Arakcheev

Попов

et al. 2019

J. Phys.: Conf. Ser.

View full text Add to dashboard Cite

The work is devoted to the numerical implementation of the tungsten evaporation process model. The tungsten evaporation model is based on solving the two-phase Stefan problem for temperature in the sample area and gas dynamics equations over the sample. The calculation results for parameters corresponding to those used on the BETA facility at BINP SB RAS show that it is possible to use the boundary homogeneous conditions of the Neumann for the velocity when setting the gas density on the plate surface.

show abstract

Numerical implementation of the Lame equation with complex boundary conditions

Sorokin

Maksimova

Lazareva

et al. 2019

J. Phys.: Conf. Ser.

View full text Add to dashboard Cite

A discrete model is constructed for calculating the Lame equation with complex boundary conditions. The model is tested on an analytical solution. A complex boundary condition arises when a microcrack is specified on one of the boundaries. Calculation of microcracks will enable better assessment of the relevance of the simulation and finding out which mechanisms will occur in the case of plasma flow heating in modern plasma and future thermonuclear installations.

show abstract

On the mechanism of surface-parallel cracks formation under pulsed heat loads

Cited by 4 publications

References 8 publications

Experimental and simulation studies on damage mechanisms of tungsten and molybdenum under compressed plasma flow irradiation

Experimental and simulation studies on damage mechanisms of tungsten and molybdenum under compressed plasma flow irradiation

Estimation of the change in the gas flow rate from the surface of a tungsten plate under pulsed heat load

Numerical implementation of the Lame equation with complex boundary conditions

Contact Info

Product

Resources

About