Pressure Generation above 35GPa in a Walker-Type Large-Volume Press*

Abstract

Pressure generation to a higher pressure range in a large-volume press (LVP) denotes our ability to explore more functional materials and deeper Earth’s interior. Pressure generated by normal tungsten carbide (WC) anvils in a commercial way is mostly limited to 25GPa in LVPs due to the limitation of their hardness and design of cell assemblies. We adopt three newly developed WC anvils for ultrahigh pressure generation in a Walker-type LVP with a maximum press load of 1000 ton. The hardest ZK01F WC anvils exhibit the highest efficiency of pressure generation than ZK10F and ZK20F WC anvils, which is related to their performances of plastic deformations. Pressure up to 35GPa at room temperature is achieved at a relatively low press load of 4.5MN by adopting the hardest ZK01F WC anvils with three tapering surfaces in conjunction with an optimized cell assembly, while pressure above 35GPa at 1700K is achieved at a higher press load of 7.5MN. Temperature above 2000K can be generated by our cell assemblies at pressure below 30GPa. We adopt such high-pressure and high-temperature techniques to fabricate several high-quality and well-sintered polycrystalline minerals for practical use. The present development of high-pressure techniques expands the pressure and temperature ranges in Walker-type LVPs and has wide applications in physics, materials, chemistry, and Earth science.