Tungsten-copper Divertor Development For EAST

1. Tungsten-copper Divertor Development For EAST Present by D. -M. Yao EAST-Divertor Group, ASIPP-Hefei, China 25th Symposium on Fusion Engineering June 10-14, 2013, San Francisco, US

2. Outline • Plasma-facing components for EAST • Necessity of W/Cu Divertor for EAST • Structural design, R&D for the W/Cu divertor • ITER-like mono-block W/Cu-PFCs development • Flat-type W/Cu-PFCs development • Summary 25th SOFE, San Francisco US, June 10-14, 2013

3. PFC for EAST The EAST tokamak 6 campaigns operation，PFCs have been upgraded in deferent stage. Mo movable poloidal limiter + Stainless Steel PFCs for First Plasma and first campaign operation 25th SOFE, San Francisco US, June 10-14, 2013

4. PFC for EAST 2008-2011 2012 Full C PFC Mo First Wall + C Divrertor Active water-cooled PFC Tolerable heat flux <2MW/m2 25th SOFE, San Francisco US, June 10-14, 2013

5. Necessity of W/Cu Divertor In the past years, the plasma heating power for EAST does not exceed 10 MW. Simulation results of divertor heat flux summarized as Below: 25th SOFE, San Francisco US, June 10-14, 2013

6. Necessity of W/Cu Divertor The heating power will be rapid increased to 20MW L-Mode H-Mode 25th SOFE, San Francisco US, June 10-14, 2013

7. W/Cu Divertor Project Target: W monoblock • Divertor • ITER-like configuration and structure, i.e., Monoblock targets (~10MW/m2) and W Flat-type dome and baffler (3~5MW/m2) • First wall • Mo +CVD-W or W flat type • Max. heat flux capability 1~3MW/m2 • Schedule • 2013-2014 • WUdiv + CLdiv + Mo (+ a new upper cryopump) • 2015-2016 • Wdiv + MoFW +WFW(depends) 2013 upper-div: W monoblock and flat-type FW: Mo tiles 2013 low-div: Carbon tiles 25th SOFE, San Francisco US, June 10-14, 2013

8. Structure design – supports Middle support Outer support Poster: TPO-110 Zibo Zhou Inner support 25th SOFE, San Francisco US, June 10-14, 2013

9. Structure design – PFUs/CB Compact end-boxes for cooling connects Monoblock- W/Cu targets End-boxes End-boxes Monoblock units ×4-5 Flat type W of ~2mm thick • ~15,000 monoblocks • 720 monoblock-units • 240 flat-type mockups • E-beam employed for CuCrZr welding Coolant from Cassette body End-box design 25th SOFE, San Francisco US, June 10-14, 2013

10. Structure design – CB assembly • Tolerance of plasma- • facing surface: • toroidal: 2mm; • neighbor: 0.5mm 25th SOFE, San Francisco US, June 10-14, 2013

11. Structure design – cooling • Requirements for cooling • Surface temperature of W monoblock < 1200 ℃ • Maximum temperature of CuCrZr < 500 ℃ • Water coolant, inlet temperature 20 ℃, and temperature rise < 70 ℃, to avoid boiling(total length a set of PFU: 1329mm) 25th SOFE, San Francisco US, June 10-14, 2013

12. R & D for structure/assembly VV simulator for assembly of supports + CBs 25th SOFE, San Francisco US, June 10-14, 2013

13. ITER-like W/Cu monoblocks • ITER grade W has been manufactured in batch scale in Chinese Company • W/Cu monoblocks: W&Cu bonded employing HIP technology 25th SOFE, San Francisco US, June 10-14, 2013

14. ITER-like Monoblock W/Cu PFMC W/Cu mockup with W tiles was manufactured successfully by Hot Radial Pressing (HRP), showing good bonding between monoblocks and CuCrZr tube. HIP The testing W/Cu mockup with W monoblock tiles was manufactured by Hot Isostatic Pressing (HIP). And also successed. • Innovative technology combinations • HIP + HIP • HIP + HRP 25th SOFE, San Francisco US, June 10-14, 2013

15. HIP+HIP/HRP HIP+HIP EAST design =================================================== HIP+HRP w/ 34 W-monoblocks ITER qualification mockup 25th SOFE, San Francisco US, June 10-14, 2013

16. Flat-type W/Cu PFMC HIP / VHP VPS / CVD or gradient W/Cu layer VHP Flat-type W/Cu mockups have been being manufactured by means of various technologies HIP & VHP: Step1:The interface of W/Cu were joined by HIP or vacuum hot pressing (VHP) at higher temperature of ~900 ℃, Step2: the interface of Cu/CuCrZr was bonded by VHP or HIP at temperature of 500~600℃. VPS & CVD coatings: Step1:Cu/CuCrZr by VHP / HIP, Step2: coating W on Cu. 25th SOFE, San Francisco US, June 10-14, 2013

17. VPS/CVD-W & Castellation CVD-W: WF6+3H2→W+6HF 0.3~0.5mm/h, porosity <1%,99.999wt.% VPS-W W Cu W VPS-W W/Cu interlayers Cu VPS-W: porosity 5-10%,99.9wt% 25th SOFE, San Francisco US, June 10-14, 2013

18. High Heat Flux Testing A 60kW e-beam facility at SWIP Mockup by HIP + HRP 2014/9/21 25th SOFE, San Francisco US, June 10-14, 2013 17

19. Thermal fatigue testing Cycles 1-2 Cycles 999-1000 Cycle 1 Cycle 1000 • Heat load ~ 8.4MW/m2, cooling water of 2m/s, 20℃, 15s/15s on/off cycles. • The mock up survived up to 1000 cycles, with surface temperature up to 1150℃. • The temperature difference of cooling water between inlet and outlet raised up to 18℃. 25th SOFE, San Francisco US, June 10-14, 2013

20. Ultrasonic NDT for monoblock-PFCs Single reflector sensor, spiral scanning ultrasonic inspection of W/Cu interface Defects > f2mm W Developed phased array, rotating reflector ultrasonic NDT inspection technologies. Cu 25th SOFE, San Francisco US, June 10-14, 2013

21. Prototype Prototype of EAST divertor W/Cu armour was developed 25th SOFE, San Francisco US, June 10-14, 2013

22. Summary • The EAST Plasma H&CD power will be increased to 20MW in near future years, EAST upper divertor is being upgrade to ITER-like. • Structure design,and R & D has been finished batch manufacture has been satrted. • First Cassette body and first plasma facing units have been made. • The ITER-like W divertor expect operate before end of 2013 25th SOFE, San Francisco US, June 10-14, 2013

23. Thanks for your attention! 25th SOFE, San Francisco US, June 10-14, 2013