Kurt Leinenweber – Arizona State University COMPRES Annual Meeting 2004 – Lake Tahoe, CA ~ June 21, 2004 Page 1 COMPRES Multi-anvil cell assembly development Kurt Leinenweber, James Tyburczy (Arizona State University)

Kurt Leinenweber – Arizona State University COMPRES Annual Meeting 2004 – Lake Tahoe, CA ~ June 21, 2004 Page 2 Some collaborators: »Caltech (Jed Mosenfelder) 14/8, 8/3 (requested) »Case Western (Jim Van Orman) 8/3 »Canberra (Tom Sharp) 8/3 »American Museum of Natural History (Rondi Davies) 8/3 »Urbana Champaign (Jie Li) 8/3 »Carnegie (Yingwei Fei, Shantanu Keshav and Alexandre Corgne) 8/3 »Stony Brook (Jiuhua Chen) 6 mm mullite cubes on order; 8/3 request; 8 mm mullite cut

Kurt Leinenweber – Arizona State University COMPRES Annual Meeting 2004 – Lake Tahoe, CA ~ June 21, 2004 Page 3 Some more collaborators: »Daresbury (David Price, Ray Jones, Ed Bailey). In- situ calibration of “hybrid” assemblies »Argonne (Yanbin Wang) In-situ calibration of “opaque” assemblies. (At ASU: development of 8/3, 10/5, 14/8 assemblies)

Kurt Leinenweber – Arizona State University COMPRES Annual Meeting 2004 – Lake Tahoe, CA ~ June 21, 2004 Page 4 Design considerations Try to achieve: 1.High precision. 2.High success rates. 3.Low cost, ready availability. 4.Consistency between laboratories. 5.Consistency over time. The best developments are those that have many or all of these characteristics at once.

Kurt Leinenweber – Arizona State University COMPRES Annual Meeting 2004 – Lake Tahoe, CA ~ June 21, 2004 Page 5 Steps to increase precision »Think about all the variables that could affect the pressure. »Eliminate them if possible. Gasket placement could affect the pressure.Problem avoided by using pre-cut paper.

Kurt Leinenweber – Arizona State University COMPRES Annual Meeting 2004 – Lake Tahoe, CA ~ June 21, 2004 Page 6 Precision (cont.) » Octahedron injection- molded. » Rhenium furnace cut by EDM. » LaCrO 3 sleeve turned and slotted by lathe. » Alumina inner pieces made on a dicing saw.

Kurt Leinenweber – Arizona State University COMPRES Annual Meeting 2004 – Lake Tahoe, CA ~ June 21, 2004 Page 7

Kurt Leinenweber – Arizona State University COMPRES Annual Meeting 2004 – Lake Tahoe, CA ~ June 21, 2004 Page 8 Steps to increase success rates » Obtain a more exact description of popular “lore”. » Keep track of success rates for different configurations - change them if the success rate could be higher. » Also: good fit of octahedron and gaskets; use of “nesting plates.” Pre-slotted octahedron (new)

Kurt Leinenweber – Arizona State University COMPRES Annual Meeting 2004 – Lake Tahoe, CA ~ June 21, 2004 Page 9 New pressure media Injection-molded octahedra (MgO/spinel). Also: mullite cubes are being made for the DIA.

Kurt Leinenweber – Arizona State University COMPRES Annual Meeting 2004 – Lake Tahoe, CA ~ June 21, 2004 Page 10 Automated lathe Slotting a lanthanum chromite sleeve Lathe (note the hood attachment!)

Kurt Leinenweber – Arizona State University COMPRES Annual Meeting 2004 – Lake Tahoe, CA ~ June 21, 2004 Page 11 Gaskets! »The current rate-limiting step for this project! »We are improving our automated milling, and testing laser-cutting. The best technique will depend on the size (smaller gaskets: laser. Larger gaskets: milling).

Kurt Leinenweber – Arizona State University COMPRES Annual Meeting 2004 – Lake Tahoe, CA ~ June 21, 2004 Page 12 Consistency between laboratories Strain cube

Kurt Leinenweber – Arizona State University COMPRES Annual Meeting 2004 – Lake Tahoe, CA ~ June 21, 2004 Page 13

Kurt Leinenweber – Arizona State University COMPRES Annual Meeting 2004 – Lake Tahoe, CA ~ June 21, 2004 Page 14 Consistency over time Document the sources of materials, and their properties (composition, density, dimensions, etc.). Beware of products that may be discontinued!

Kurt Leinenweber – Arizona State University COMPRES Annual Meeting 2004 – Lake Tahoe, CA ~ June 21, 2004 Page 15 Upcoming developments: »Develop 10/5, 18/11, and 25/15 COMPRES assemblies. »New 14/8: “zero thermal gradient, x-ray transparent” assembly with smaller pressure loss at very high T. »New ceramics: In hand: forsterite insulation, spinel insulation, TiB 2 /BN machinable composite furnace, mullite pressure medium. In development or proposed: TiO 2 insulation, SiC furnace. »(Also could use: a better pressure standard for temperatures above °C).

Kurt Leinenweber – Arizona State University COMPRES Annual Meeting 2004 – Lake Tahoe, CA ~ June 21, 2004 Page 16 Upcoming plans: »Hands-on training course at Argonne (joint between this project and Y. Wang). (not during Sept shutdown or Dec/Jan holidays at Argonne). »Cell design “summit meeting” in Arizona? »Continued collaborations, developments, and data gathering with the COMPRES assemblies.