Shock Melting Temperature of Initially Porous Iron andIndication for Melting Curve of Iron at High Pressures

Abstract

The melting curve of iron is crucial for modelling of the earth's internal heatstructures and to understand melting of solids at high pressures.However, the measured melting temperatures of iron at high pressuresare disparate so far. We measured the shocked interface (porousiron/sapphire window) temperatures of a kind of porous iron. By using amodel for shock temperature measurement [High Pressures Res. 2 (1990)159] and the previous results of sound velocity measurements [Chin.Phys. Lett. 18 (2001) 852], we determine the melting temperatures ofiron at shock compression high pressures of 145 and 171 GPa. They areconsistent with the results reported by other shock compressionexperiments. Based on the possible different melting mechanisms of ironin diamond anvil cell and in shock compression, the corrected meltingtemperatures of iron at high pressures become more consistent.