External resistive heating for the diamond anvil cell can generate a homogeneous temperature field across the sample chamber, with reliable temperatures measured by thermocouple, and plays an important role in high pressure high temperature experimental work. On beamline 1222, ALS, there are two kinds of external resistive heaters available for users: band heaters and a ring heater.
Band Heater
The band heater at BL1222 is a low maintenance/support user facilities for BX90 cells, symmetric cells and other typical sizes of diamond anvil cells up to 900K, and the newly developed Labview code is user friendly.
The above three pictures demonstrate the how to mount a BX90 DAC inside a band heater, and what it looks like after a membrane is added to a diamond anvil cell, and what it looks like after a reduced protection can is mounted.
A newly developed Labview code allow users easily to set the target temperature, and start to heat.
A typical power vs temperature of typical BX90 cell shows that the band heater can heat sample in a sample chamber up to 900K.
Ring heater
The ring heater is made of tungsten wire, alumina ceramic, and is designed for the BX90 cell only. It can heat the sample in the DAC up to 1700K. In addition, the ring heater is equipped with a membrane, and is employed in a protective reduced gas environment.
The following picture shows how the ring heater looks like, how the ring heater fit a typical BX90 cell, and how the membrane and a protection can looks like.
The Tungsten heater can heat the sample inside sample chamber up to 1700K
The ring heater is capable to conduct melting experiments, and other heating at elevated pressure.
