1. CLIC Meeting 21/08/2001 G. Arnau Izquierdo EST/SM 1 Electropolishing of W irises. SEM images. 1) Manufacturing ways. 2) CERN Workshop iris images. 3) Flueckiger iris images. 4) Plansee iris images. 5) Conclusions.

2. CLIC Meeting 21/08/2001G. Arnau Izquierdo EST/SM2 Manufacturing ways. Sintered + Hot forged W Ø36mm rod, 99.96% purity Sintered + Hot forged W EDM EDM: Electrical Discharge Machining = Electro-erosion EP: Electropolishing EP test: - 6 µm - 7 µm Abrasive Blasting EDM Abrasive Blasting? EDM Cylindrical Grinding EP CERN Workshop FlueckigerPlansee Delivery 2 iris for delivery : - 8.5 µm & - 16.5 µm EP test: - 8 µm - 9 µm - 27 µm

3. CLIC Meeting 21/08/2001G. Arnau Izquierdo EST/SM3 CERN workshop Before Electropolishing (1/2) Edge Edge Stains Stains Flakes Flakes Blasting incrustation Blasting incrustation 400µm 50x

4. CLIC Meeting 21/08/2001G. Arnau Izquierdo EST/SM4 CERN Workshop Before Electropolishing (2/2) 20µm 100µm 1000x 200x

5. CLIC Meeting 21/08/2001G. Arnau Izquierdo EST/SM5 CERN Workshop After Electropolishing (1/2) - 8µm + - 9µm - 8µm + - 9µm Intergranular cracks Intergranular cracks Pores Pores 400µm 50x

6. CLIC Meeting 21/08/2001G. Arnau Izquierdo EST/SM6 CERN Workshop After Electropolishing (2/2) 20µm 100µm 1000x 200x

7. CLIC Meeting 21/08/2001G. Arnau Izquierdo EST/SM7 Flueckiger Before Electropolishing (1/2) Edge Edge 400µm 50x

8. CLIC Meeting 21/08/2001G. Arnau Izquierdo EST/SM8 Flueckiger Before Electropolishing (2/2) 20µm 100µm 1000x 200x

9. CLIC Meeting 21/08/2001G. Arnau Izquierdo EST/SM9 Flueckiger After Electropolishing (1/2) - 6µm + - 7µm - 6µm + - 7µm Intergranular cracks Intergranular cracks Pores Pores 400µm 50x