US1335789A - Explosive - Google Patents

Description

UNITED STATES PATENT oirrrcia.

FREDERICK MARK IBECKE'I', OF NIAGARA ELECTED METALLURGICAL COMPANY, OF A CORPORATION OF WEST VIRGINIA.

EXPLOSIVE.

No Drawing.

To all whom it may concern: f

Be it known that we, (1) JOHN R. MAR- DICK and (2) FREDERICK M. Bnonn'r, (1) acitizen of the United States and (2) a subject of the King of Great Britain, residing at (1) New York, (2) Niagara Falls, in the counties of (1) New York, (2) Niagara, and State of New York, have invented new and useful Improvements in Explosives, of which the following is a specification.

This invention relates to certain novel explosive compositions suitable for blasting and other commercial purposes, and con taining as essential components one or more normally solid nitro-aromatic bodies having at least three nitro-groups, of which trinitro-toluol (T. N. T.) and picric acid are types, associated with an oxidizing agent or agents and a magnesium-silicon alloy.

A general formula for an explosive composition embodying-our invention is as follows Combustible O- 5)? by weight Plasticizing ingredient" 1 5% by weight Anti-acid 0 1']? by weight An illustrative formula for a commercial (blasting) explosive of the plastic type, capable of being tamped into place. is as follows Picric acid or T. N. '1 1T Magnesium-silicon alloy 10 "0 Ammonium nitrate 35 {-T/p Sodium nitrate Dinitrotoluol 3 \Vood flour 3 7 Calcium carbonate 0.5% Each of the essential components of the explosive, performs a function in the mixture. and the. proportions of the components will be varied in practice as may be necessa to the proper performance of this function, having in view the specific puppose for which the explosive is intended. I

The nitro-aromatic bodies are normally solid but readily fusible, and are therefore easily compounded with the other ingredients, yielding cohesive plastic compositions which are readily tamped into conformity Specification of Letters Patent.

Application filed June 19,

Patented Apr.6,1920.

1918. Serial No. 240,793.

to the bore. Instead of T. N. T. or picric acid I may use other nitro-aromatic bodies having similar desirable qualities, as for example triand tetra-nitro-naphthalene, and the tri-nitro cresols,

The oxidizer is in sufiicient proportion to convert any carbon monoxid into carbon dioxid and serves in general to oxidize all poisonous or objectionable gases or compounds, rendering the products of explosion innocuous. It is also used in sufficient excess to etfect oxidation of the paraflined paper wrapper usually employed. The wood flour or other combustible will unite with any otherwise unconsumed excess of the oxidizing component. The use of the antiacid body is precautionary, guarding against development from any cause of an acid condition in the mixture.

In case a hygroscopic salt such as ammonium nitrate is used I prefer to introduce into the mixture small proportions, say four per cent. or less, of a. liquid capable of coating the salt-and thereby protecting it from atmospheric moisture. For this purpose I may use Vaseline, oils, etc.; but I prefer liquid nitro bodies such for example as the -liquid nitro xylenes, o-dinitro benzene, di-

nitro toluene or the like. These liquid nitro bodies act as deadenin agents, and therefore should not be used in excessive proportions.

A primary advantage 'of the introduction of magnesium into explosive mixtures fol lows from the great amount of heat liberated in course of its combination with oxygen. Magnesium metal however particularly when very finely subdivided and when existing under the conditions obtaining in the explosive mixture, is somewhat lacking in stability and liable to slow oxidation. It has been found on the other hand that the magnesium-silicon alloys are sufiiciently stable to permit of such use. In this respect the magnesium-silicon alloys are sharply differentiated from such alloys as those of silicon with calcium. For example calcium silicide corresponding substantially to the formula CaSi is a tairl stable compound, but alloys of calcium and silicon containing a materially higher proportion of calcium than the above are coni mratively unstable; consequently it has not proven practicable to increase the power of explosive mixtures sufficient stability containing calcium and silicon by increasing the calcium content of the alloy component. This does not apply however to the magnesium-silicon alloys, which possess a sulficient degree of stability for the purposes 1ndicated even when the magnesium content is decidedly higher than corresponds to the known silicide MgSi. Such compounds, 1

respective of the presence or absence of iron or other components, may be defined as alloys in which the magnesium is in excess of the equimolecular con.

A further advantage in the use of magnesium-silicon alloys arises as follows The magnesium component of the alloy requires for its oxidation only about one-half of the oxygen required by the silicon component. It follows from this that the higher the relative proportion of magnesium in the alloy, the larger the permissible proportion of the alloy in the explosive mixture. It is therefore of great advantage in this connection that the magnesiumsilicon alloys containing more than the equimolecular proportion of magnesium possess for use in explosive comproportion to the silipositions.

Other advantages arising from the use of magnesium-silicon alloys in compositions of the kind above indicated follow from the relative lightness of these alloys and from the fact that the alloys are relatively brittle as compared with metallic magnesium, and are hence more easily pulverized to the requisite degree of fineness. I It will of course be understood that it is Within our invention to use-silicon in other reduced forms, for example as ferro-silicon, in conjunction with or in part replacement of the magnesium-silicon alloys. For example our invention contemplates the complete or partial replacement of. ferro-silicon by magnesium-silicon alloys in such formulae as are disclosed in the copending application of John R. Mardick, Serial No. 207,389, filed December 15, 1917. Nor is our invention restricted to the use of magne sium-silicon alloys in which the magnesium tro-body, and

exists in higher proportions to the silicon than the equimolecular proportion; although we prefer in all cases to use alloys containing such higher proportions of magnesium.

' We claim v l. A commercial explosive containing nitro-aromatic' body, an oxidizer, and magnesium-silicon alloy.

2. A- commercial explosive containing a nitro-aromatic body, an oxidizer, and a magnesium-silicon alloy in which the magnesium is in excess of the equimolecular proportion to the silicon.

3. A commercial explosive containing a nitro-aromatic body having at least three nitro-groups, an oxidizer, and a magnesiumsilicon alloy.

4:. A commercial explosive containing a nitro-aromatic body having at least three nitro-groups, an oxidizer, and a magnesiunr silicon alloy in which the magnesium is in excess of the equimolecular proportion to the silicon.

5. A commercial explosive containing a nitro-aromatic body having at least three nitro-groups, an oxidizer, a plasticizing ingredient, and amagnesium-silicon alloy.

6. A commercial explosive containing a -n itro-aromatic body having at least three intro-groups, an oxidizer, a plasticizing ingredient, and a magnesium-silicon alloy in which the magnesium is in excess of the equimolecular proportion to the silicon.

7. A commercial explosive containing a nitro-aromatic body having at least three nitro-groups, an oxidizer, a plasticizing nia magnesium-silicon alloy. 8. A commercial explosive containing a nitro-aromatic body having at least three nitro-groups, an oxidizer, a plasticizing nitro-body, and a magnesium-silicon alloy in which the magnesium is in excess of the equimolecular proportion to the silicon.

In testimony whereof, we aflix our signatures.

JOHN R. MARDICK. FREDERICK MARK BEGKET.