Designing multi-anvil assemblies: The COMPRES cell assembly project Kurt Leinenweber Page 1 of 24 Page 2 of 24 Challenges: • Thermocouple has to work well • Wide range of P and T desirable for each assembly • Easy to assemble • Not expensive • Specs have to be repeatable from year to year (well-documented) Page 3 of 24 Five sizes of octahedra - 8 mm, 10 mm, 14 mm, 18 mm and 25 mm - used in the COMPRES assemblies. Page 4 of 24 The octahedra showing the sample holes already molded in. Page 5 of 24 Gasketing Gasket setup using pre-cut paper and pre-milled gaskets, shown on the bottom 4 cubes of the “nest.” Page 6 of 24 Gasketing (cont.) Pre-cut paper that is used to position the gaskets. Page 7 of 24 Gasketing (cont.) ASU’s shop foreman, Rick Flubacher, and an automated mill. Page 8 of 24 Gasketing (cont.) Trial milling of pyrophyllite gaskets on a programmable mill. Page 9 of 24 Gasketing (cont.) COMPRES machinist, Brian Nagy, and the COMPRES automated lathe. Page 10 of 24 Assembly Cutting thermocouple slots in a lanthanum chromite sleeve for the 8/3 assembly on the automated lathe. Page 11 of 24 Assembly (cont.) Rhenium furnace (size 5.4 mm by 8 mm) cut using wire EDM (Electrical Discharge Machining), for the 8/3 assembly. Page 12 of 24 Assembly (cont.) The 8/3 assembly with the lanthanum chromite sleeve and the rhenium furnace in place. Page 13 of 24 Modification for x-ray Beam path (green) through the 8/3 assembly (courtesy of Emmanuel Soignard). Page 14 of 24 Modification for x-ray (cont.) NEW: Special rhenium furnace design for in-situ x-ray experiments in the 8/3 assembly, including a central slit for the x-ray beam. Page 15 of 24 Testing “COMPRES care packages” ready for shipping. Page 16 of 24 Testing (cont). “Big blue” multi-anvil at ASU (frame is from Clifton Fluid Power, Inc.; module made in-house). Page 17 of 24 Testing (cont). 14/8 “G2” assembly after squeezing. Page 18 of 24 Results for three “locked” assemblies • Calibration curves • Success rates • Suitability for offline and in-situ work • (note: because development of too many new things can be confusing, we “lock” certain designs so that they won’t change, while we continue to develop others). Page 19 of 24 14/8 “Caltech” assembly 14/8 “Caltech” assembly (lanthanum chromite step-heater) Page 20 of 24 14/8 “Caltech” assembly thermal profile Page 21 of 24 14/8 “G2” assembly Page 22 of 24 8/3 assembly Page 23 of 24 8/3 assembly (cont): room temperature calibration. Page 24 of 24 8/3 assembly (cont.): Thermal profile. Page 25 of 24 8/3 assembly (cont.) Effect of temperature on pressure. Page 26 of 24 10/5 “Tami” assembly 10/5 Power Curve from APS experiments 500 450 400 Power (W) 350 300 T0556 T0558 T0560 250 200 150 100 50 0 0 200 400 600 800 1000 Temperature (oC) Page 27 of 24 1200 1400 1600 10/5 “Tami” assembly (cont.): Pressure calibration Pressure Calibration of 10/5 Assembly (CsCl pressure standard) 25 Pressure (GPa) 20 1000oC 25oC 15 10 5 0 0 100 200 300 400 Force (Tons) Page 28 of 24 500 600 700 800 10/5 assembly (cont.): Effect of temperature on pressure Effect of temperature on pressure of 10/5 assembly (CsCl pressure standard) 22 700 tons Pressure (GPa) 20 500 tons 18 400 tons 16 14 12 10 0 200 400 600 800 Temperature (oC) Page 29 of 24 1000 1200 1400 1600