2,982,641 United States Patent Office Patented May 2, 1961 2 Example 2: 2,982,641 Ammonium nitrate------40 TNT ------40 ALUMNIZED EXPLOSIVES Aluminum (finely divided) ------18 John W. Dawson, Philadelphia, Pa., and Frank H. West 5 Magnesium nitrate (anhydrous or monohydrate, heimer, Chicago, Ill., assignors, by mesne assignments, finely divided).------4 to the United States of America as represented by the Example 3: Secretary of the Navy TNT ------80 Aluminum (finely divided).------20 No Drawing. Fied May 6, 1946, Ser. No. 667,732 0 Calcium chloride (anhydrous, finely divided).-- 0.5 3 Claims. (C. 52-6) Example 4: RDX ------42 TNT ------40 This invention relates to aluminized explosives, i.e., ex Aluminum (finely divided).------18 plosives which contain powdered aluminum as one of 5 Wax ------4. their principal components, such as those known in the Nitrocellulose ------0.7 art as Torpex and Minol; the invention pertains partic Lecithin ------0-2 ularly to aluminized explosives which are conditioned to Calcium chloride (anhydrous, finely divided) -- 0.5 pour into a container without spewing and to generate only an inappreciable quantity of gas in the enclosed 20 In all of the above examples, the explosive composition container. exhibited a greatly reduced tendency to spew and to gen An obvious disadvantage to aluminized explosives erate gas both while the pouring operation was being con which have a tendency to spew is the accompanying dif ducted and also after the explosive had been introduced ficulty with which such explosives are loaded into con into a projectile or mine body. In the case of Example tainers. The marked tendency for these aluminized ex 25 4 in which wax was used as a desensitizing agent, little plosives to generate gas, even when in the solid form, is or no wax was seen to exude from the explosive case. It another disadvantage of previously used aluminized ex should be noted that in all of the above examples there plosives since the pressure thus generated inside the con was no perceptible change in sensitivity of explosive tainer may grow to the point where it is capable of col caused by the addition of the hydrophilic or desiccating lapsing the booster cavity, or some similar weak struc 30 agent. ture within the container assembly. Moreover, in the Although we prefer to employ magnesium nitrate, case of Torpex some of the gas generated is hydrogen calcium cloride or magnesium perchlorate as the desiccat and thus represents a fire hazard. Presumably, this gas ing agents with our improved aluminized explosives, and is generated by the action of moisture on aluminum or have limited the examples herein to those agents, we do other constituents of the explosive mixture. . 35 not intend so to limit our invention, for it is obvious that It is known that aluminized explosives may be de other desiccating or hydrophilic agents may be effectively sensitized with wax and this practice has been almost used in this manner. Moreover, we do not intend to be universally adopted by the ordnance profession. The limited closely to the preferred proportions in which our wax, however, has a tendency to exude at moderately desiccants have been used, as set forth in the examples, high storage temperatures, for example 60 degrees C., 40 since the effectiveness of the desiccant to perform its ap such as might be found in the holds of ships or in the pointed function is manifestly dependent upon the tropics. quantity used and may be varied widely according to the We have found that the tendency of aluminized ex preference of the individual employing the invention. plosive compositions to generate gas is greatly reduced We claim: or eliminated by the addition thereto of a hydrophilic or 1. A cast composition consisting essentially of at least desiccating agent, such as magnesium nitrate, calcium 45 18 parts by weight of powdered aluminum, a minor por chloride, or magnesium perchlorate. tion varying from 2 to 4 parts by weight of a desiccant The mechanism by which the hydrophilic agent inhibits Selected from the group consisting of anhydrous calcium the generation of gas is believed to be a hydration reaction chloride, magnesium nitrate, and magnesium perchlorate, whereby the moisture contained in the explosive mixture and at least 80 parts by weight of an explosive containing is chemically combined with the hydrophilic agent to 50 at least 40 parts by weight of trinitrotoluene. form a hydrate thereof, thus rendering the water incapable 2. A cast composition consisting essentially of about of reacting with the aluminum to form a gas. As a fur 20 parts by weight of powdered aluminum, about 4 part ther consequence of this gas-inhibiting reaction, it has by Weight of powdered anhydrous calcium chloride, and been found that aluminized explosives which have been about 82 parts by weight of an explosive containing ap desensitized with wax, exhibit a considerably smaller ten 55 proximately 42 parts cyclonite and 40 parts of trinitro dency to exude even at moderately high storage tempera toluene. tures. It is believed that this advantage results from the 3. A cast composition consisting essentially of about fact that the hydrophilic agent reduces the gas evolved 20 parts by weight of powdered aluminum, about a part. from the explosive, and that when little or no gas is thus by weight of powdered anhydrous calcium chloride, and generated the tendency for the wax to exude is reduced. 60 about 80 parts by weight of an explosive containing ap In the following examples of aluminized explosives proximately 40 parts of ammonium nitrate and 40 parts made in accordance with the present invention, it will be of trinitrotoluene. understood that the term RDX is a short designation for cyclotrimethylenetrinitramine (also known as cyclonite), References Cited in the file of this patent and that the term TNT is the short designation for trini UNITED STATES PATENTS trotoluene. 857,580 Bowen ------June 25, 1907 Example 1: 2,344,840 Watt ------Mar. 21, 1944 RDX ------'um an are a norman may names as a main a mas 42 2,369,517 Bagley ------Feb. 13, 1945 TNT ------40 Aluminum (finely divided).------18 70 FOREIGN PATENTs Calcium chloride (anhydrous, finely divided).-- 0.5 22,030 Great Britain ------1910