Extreme Pressure Diamond Anvil Cell Laboratory

Function. The exhaustive investigation of different materials at ultrahigh pressures by using the shear diamond anvil cell (SDAC).

The shear diamond anvil cell

The basic characteristics: the range of pressure: up to 100 GPa±0.1 Gpa (maximum); up to 60 GPa±0.1 Gpa (routine usage); measuring the sample thickness from 1 mm to 500 mm ±0.5mm during its loading; the dimensions of the SDAC are 130x100x70 mm; the weight is up to 1кg.

Special features:
1. The diamond anvils

• the weight 0.2 - 0.5 carat;
• 16, 24 or 32 facets;
• the culet diameters 0.3 - 0.6 mm;
• to choose anvils with the least birefringence and fluorescence;
• the optimum design according to requirements.

2. The loading facility

• the loading nut;
• the package disk springs with the squeezed force up to 800 kg;
• the transmitting force lever of 2 sort with the proportion lever arms 1:4.

3. The high pressure unit

• this design allows to turn of the one diamond anvil about another up to 360 degree around of the loading application axis;
• there is a slot in one of the plate of fastening diamond anvils for X-ray diffraction in situ.

4. The facility for thickness measuring of a tested sample

• · this design allows to measure both of the tested sample thickness and the nonparallelism of the diamond anvil culet faces within of an 1 of arc minute during loading of a tested sample.

The basic distinctive features:

1. Opportunity of making in a tested sample both high static pressure and shift strain.
2. Opportunity of making in a tested sample the hydrostatic requirements by using a gasket and a transmitting pressure fluid or nonhydrostatic with a lapse rate of pressure.
3. Measuring the sample thickness during its loading.
4. Measuring the nonparallelism of the diamond anvil culet faces within of an 1 of arc minute allows:
   • to check an alignment of the SDAC during its loading;
   • to eliminate completely a possibility of the fracture diamond anvils along of the breaking alignment;
   • to reduce considerably expenditures for carrying out investigations;
   • · to carry out an initial alignment of the SDAC within more accuracy without usage of the interference fringes.

1. Measuring of pressure by a ruby scale in a hand-operated or an automatic mode. The automatic mode is applied at measuring allocation of pressure on the area of a tested sample without gasket at presence of a pressure gradient by using the computer and 2 step motors with accuracy to 1mm.
2. . The phase changes in a tested sample are observed in transiting and reflection light by using the microscope and digital video interfaced with the computer.

The recent development

For the first time, borazon is obtained by using SDAC at pressure 5.6 GPa and room temperature.

Possible views of cooperation

1. Calculating and making diamond anvils of an optimum design.

2. Carrying out of joint investigations of different materials by using our equipments.

3. Designing and making DAC.

4. Designing and making installation of measuring pressure.

Contact address:
Dr. Leonid K. Shvedov
Dr. Sergey B. Polotnyak
Bakul Institute for Superhard Materials
National Academy of Sciences of Ukraine
2, Avtozavodskaya St.
254074 Kiev Ukraine
Tel/Fax: +380-044-4688625, E-mail: alcon@ism.kiev.ua