Extended Data Fig. 9: Schematic showing the fabrication of U-shaped channels.
From: Inhibiting the Leidenfrost effect above 1,000 °C for sustained thermal cooling
a. Fabrication of U-shaped channels with different heights (50 µm, 100 µm, 120 µm). Arc-shaped grooves with a height of 50 µm, 100 µm and 120 µm are obtained with a flat milling cutter with a tip diameter of 300 µm that provides grooves with a depth of 340 µm, 290 µm and 270 µm, respectively, as shown in Steps 1–3. Then, the flat bottom cutter is replaced with a ball nose cutter with a diameter of 200 µm to further fit the profile of the arcs, as shown in Steps 4-5. b. Making pillars with a wire electrical discharge machine (WEDM). In Step 1, the steel workpiece moves under the molybdenum wire with a diameter of 180 µm, which results in U-shaped grooves. Then, the workpiece is rotated by 90o and Step 1 is repeated. The current, voltage and machining compensation are 2 A, 80 V and 80 µm, respectively.
