Non-destructive methods for the defect detection in the ITER high heat flux components

This paper focuses on the development of the water-cooled divertor target concept known as Thermal Break, which was carried out in two phases. In Phase 1, six small scale mock-ups were fabricated and subjected to high heat flux (HHF) testing of up to 25 MW/m 2 and thermal cycling of up to 500 cycles at 20 MW/m 2. All six mock-ups survived the campaign and maintained 20 MW/m 2 heat exhaust capability. Detailed examination of mock-ups was carried out to understand the damage mechanisms. One mock-up, which was tested beyond its design intent at 500 cycles, shows signs of progressive damage. Potential damage modes were identified and influenced subsequent Phase 2 mock-up design. Although there are signs of tungsten surface cracking, the predominant damage mode is not by "deep cracking" but substantial permanent deformation in the interlayer features. Therefore, in Phase 2 the manufacturing procedure was updated, the interlayer grooves were given stress-relieving radii which have significantly reduced the interlayer plastic strain range. Interlayer design parameters were selected following the use of response surface-based design search and optimization. Mock-ups of the Phase 2 design have been manufactured and HHF testing is planned within 2018.

show abstract

“…1). After HHF testing, the mock-up was inspected using non-destructive ultrasonic imaging at ENEA Frascati (Italy) [7], (see for example Fig. 2).…”

Section: Phase 1 Post Hhf Test Resultsmentioning

confidence: 99%

High heat flux test results for a thermal break DEMO divertor target and subsequent design and manufacture development

Lukenskas

Barrett

Fursdon

et al. 2019

Fusion Engineering and Design

Self Cite

View full text Add to dashboard Cite

show abstract

“…The power density, with this assumption, is of the order of 20 MW m −2 , compatible with the monoblock W tiles. Extensive tests [25,26] on these tiles have been performed; in particular 1000 cycles of 15 s heating and 15 s cooling were performed under a load up to 20 MW m −2 . The results have indicated the onset of minor cracks, appearing only for the case of 20 MW m −2 , when the number of cycles was approaching the 1000.…”

Section: Divertor Designmentioning

confidence: 99%

FAST: A European ITER satellite experiment in the view of DEMO

Crisanti

Cucchiaro

Albanese

et al. 2011

Fusion Engineering and Design

Self Cite

View full text Add to dashboard Cite

Comparison of X-ray and neutron tomographic imaging to qualify manufacturing of a fusion divertor tungsten monoblock

Evans

Minniti

Fursdon

et al. 2018

Fusion Engineering and Design

View full text Add to dashboard Cite

Within a tokamak fusion energy device, the performance and lifespan of a divertor monoblock under high heat flux cycles is of particular interest. Key to this is the quality of manufacture, especially the material joining interfaces. Presented here is a comparative study between X-ray and neutron tomography to investigate the quality of manufactured monoblocks. Tungsten is a high attenuator of X-rays, thus X-ray tomography was performed on 'region of interest' samples where the majority of the tungsten armour was removed to reduce the attenuation path. Neutron tomography was performed on the full monoblock samples for non-destructive testing and on the 'region of interest' samples for direct comparison. Both techniques were shown to be capable of imaging the samples but having their own advantages and disadvantages relating to image accuracy and logistical feasibility. The techniques discussed are beneficial for either the research and development cycle of fusion component design or in quality assurance of manufacturing.

show abstract

Non-destructive methods for the defect detection in the ITER high heat flux components

Cited by 5 publications

References 3 publications

High heat flux test results for a thermal break DEMO divertor target and subsequent design and manufacture development

High heat flux test results for a thermal break DEMO divertor target and subsequent design and manufacture development

FAST: A European ITER satellite experiment in the view of DEMO

Comparison of X-ray and neutron tomographic imaging to qualify manufacturing of a fusion divertor tungsten monoblock

Contact Info

Product

Resources

About