Department of Explosion

Laboratory of High-Speed Processes

Laboratory of Dynamic Loading

Super-hard materials: Cubic silicon nitride

10

100

0,1 1 10 100 1000

P, г

Hv, ГПа1 2 3

4 5 6

7

30

cc

20

50

HV, GPa

Pi, g

Shock synthesis: β-Si3N4 → c-Si3N4 ► nano-dispersive powderStatic HPHT burning: 1100°C, 5-6 GPa, 1-5 hours ► nano-bulks

Micro-hardness vs load to indenter ►

Scale – 1 mm1-3 – our, 4-5 – Japan, 6-7 – USA

2-fold harder than others

Laboratory of High-Speed Processes

Investigation of detonation and shock waves by synchrotron radiation

1-D and 2-D density distribution behind shock and detonation front

SAXS for kinetics of crystal phase and cracks growing during explosion events

Dynamic X-ray diffraction Technical data: • SR beam 15x0.1 mm in size, exposure – 1 ns, repeat – 250 ns• Energy of γ-quantum up to 20 kV• X-ray quantometer up to 256 channels• single detector 0.1 mm in width• explosive chamber up to 50 g of HE investigated

Hardware for experiments

Laboratory of Dynamic Loading

Principal research topics: Investigation of pulse loading and deformation processes of homogeneous and heterogeneous media for developing of advanced materials.

Explosive chambers: a) KV-2, max weight of explosive charge is 1 kg, b) VK-15 max weight of explosive charge is 5 kg.

Staff: 3 professors, 2 senior researchers (Ph.D), 1 research officer

ab

Equipment: explosive chambers, digital oscilloscopes, pulse generators, scanning electron microscope, optical microscopes.

Scanning electron microscope LEO-420 with X-ray microanalyser RONTEC

Explosive welding: a) fragments of heat exchanger and crystallizer, b) multi-layer composite materials.

Explosive compaction: metal-ceramic composite materials and products.

a b

Developing microcrystalline materials by dynamic methods

Fragmentation in form of block structures is visible after shock-wave loading of fine-grained materials

Microstructure of compact from internally oxidized copper alloy Cu - 0,4%Al

Grain size distribution after intensive plastic deformation in composite Cu-Al2O3

05

1015202530

0.1 0.15 0.2 0.2

5 0.3 0.35 0.4 0.4

5 0.5 0.55 0.6 0.6

5 0.7 0.75 0.8 0.8

5

Grain size - d mcm

Qua

ntity

of

grai

ns -N

The experimental set-up (a) and a photo of measuring element (b) for measurement of temperature of a metal jet. 1 – the copper cylinder with semispherical hollow, 2 - the insertion from constantan, 3 - a rod from constantan, 4 - a compound charge of explosive, 5 - a detonator.

The X-ray photograph of impact of a cumulative jet and a rod.

Measurement of a cumulative jet temperature

a b

The set-up (a) and a photo (b) of experimental assembly: 1 - a researched powder, 2 - an aluminium foil, 3 - a coil - source of a magnetic field, 4 - the measuring coil, 5 - a com-pound charge of explo-sive, 6 - a detonator.

( D - u) - the diagram of shock compression Al2O3 powder with initial density 1.06 g/sm3.

Measurement of mass velocity behind

shock wave front in powder