(1) – Russian Federal Nucler Center, Sarov, Nizhni Novgorod region, Russia (2) – Institute of Structural Mycrokinetics of Russian Academy of Sciences, Chernogolovka, Moscow Region,Russia.

In paper [1] we have investigated the explosive mixtures PETN + baking soda. In this paper we present the results of investigations of explosive mixtures of RDX – powder and baking soda. It is possible to presume that these types of mixtures can be more convenient for explosive welding of thin materials Here the results of investigations of detonation properties of the mixtures RDX powder and baking soda with different sizes of particles of RDX- powder. We shall note the mixtures RDX-soda by sign “RS”

For making of “RS 35/65” we used following components:  RDX–35%, with the sizes of crystals about 70 μm  Backing soda.  Water-solved organic color ‘rodamin’  The processes of making “RS” are following  Solution of rodamin in water with weight relation 1/1000 and then filtration  Coloring RDX crystals by solution of rodamin in water and mixing  Filtration of suspension of colored RDX in water in vacuum.  Drying of layer of RDX thickness less than 10 mm at (90±5)°С 1 hour.  Taking of soda and milling it till getting uniform small fraction.  Mechanical mixing of RDX and soda till full uniformity.  Drying of mixture “RS” layer less 10 mm at (90±5)°С not less 2 hours.  Measuring of weight and packing.

Detonation velocity was measured by contact method. The drawing of our set-up for measurement of detonation velocity is shown in Fig.1 1-detonator 2-detonating cord 3-booster 4-plate from plastic 5-contacts 6-paper box 7-explosive PS

Таble 1 Spread of detonation for mixtures RS of different compositions. № Composition of RS Thickne ss of layer mm Density of layer* g/sm 3 Path of Shock Wave t=f(x) Detonation velocity of RS, km/sec 1 50/50 100,890,694х-32,8811, ,990,4445х-16,2042, ,870,5412х-5,5281, ,910,3763х-16,0352, ,080,4018х-4,4392, ,060,3211х-6,9052, ,030,3523х-6,9833,11 825/75231,060,3566х-11,3332,8

In fig.3 are shown the plots t=f(x) from 50 mm from point of initiation for mixtures RS with thicknesses of charges from 10 to 23 mm. fig.3

The dependence of detonation velocity of RS 35/65 from thickness of charge layer and similar dependence for PS 35/65 are shown in Fig.4. RSPS The dependencies shown in Fig.4 are chcharacterisik for mixtures RS and PS. Fig.4

Fig.5 Detonation velocity vs. Thickness of layer for mixtures PS micro and RS micro RS - microPS - micro

As a results of investigations carried out for mixture of RDX micro and soda 35/65 with size of RDX about 1-3 microns is possible to make following conclusions:  The minimal detonation velocity on steel bottom is equal about 1,9 km/s at the thickness of charge 2 mm.  The interval of stabilization of detonation is about 40 mm, the velocity of stationary is 2,25-2,5 at the charge thickness about 4 mm.  The elaborated explosive mizture with density  ~0,93 g/см3 Which can detonated with obtained parameters: detonation velocity 1,9 km/sec, layer thickness 2 mm can be used for explosive welding effectively for welding of very thin layers of different metals at minimal deformation of welded parts.

 [ 1 ] A.Deribas, L.Andreevskikh, O.Drennov, A.Mikhailov, N.Titova, and L.Fomicheva “New Explosives for Explosive Welding” IX International Symposium on Explosive Prodaction of New Materials. May 6-9, Lisse, the Netherlands.