Torpex was a mixture of RDX, TNT and powered aluminium.
RDX was widely used in ww2, both by the British and the Americans. Try to put a hand on the following book: "The Secret History of RDX: The Super-Explosive that Helped Win World War II" - Colin F. Baxter, The University Press of Kentucky, 2016 - quite enjoyable to read and informative
From a ww2 US publication:
RDX (Cyclonite Cyclotrimethylenetrinitramine)
RDX is the most powerful and brisant of the military high explosives, and it is considered much too sensitive to use alone. It seems to be about half way between Tetryl and PETN in mixtures of other explosives and inerts which reduce the sensitivity to a safe range, while the mixtures have a very high brisance and power due to the RDX. It has excellent stowage qualities, but, because of its sensitivity, it is shipped immersed in water like an initiating explosive.
The velocity of detonation is 28,000 feet/second at a density of 1.70. Its Laboratory Impact Value is 34. Its Bullet Impact Value is 0. Its color is white.
Torpex
Torpex is one of the explosives developed during this war to be used mainly in underwater ordnance. The original Torpex (Torpex 1) was a mixture of 45% RDX, 37% TNT, 18% Aluminum powder (1% wax added). It is used in mines, torpedo warheads, and depth bombs. Torpex is more sensitive than TNT; its bullet impact and drop test sensitivities are of the same order as those of Tetryl. It is quite stable in stowage, though it produces gas, causing pressure in the case. It is insensitive enough to stand all normal handling. Its melting point is low enough for it to be cast-loaded.
Its velocity of detonation is 24,000 feet/second at a density of 1.72. It is 141% as powerful as TNT. Its Laboratory Impact Value is 53. Its Bullet Impact Value is 48. Its color is slate gray.
DBX (Depth Bomb Explosive)
DBX is another aluminized RDX mixture, and its name suggests its intended use. It is 21% RDX, 21% Aluminum Nitrate, 40% TNT, 18% Aluminum. It was designed to replace Torpex, which is closely resembles in sensitivity, strength, brisance, and energy of shock in water, but half of the strategic RDX in Torpex is replaced by Ammonium Nitrate in DBX. It will probably not be used, as the present supply of RDX seems adequate to meet the demand. DBX can be cast, though its melting range of 98-105 degrees Celsius is about the upper limit.
Its velocity of detonation is 22,300 feet/second at a density of 1.68. It is 143% as powerful as TNT under water. Its Laboratory Impact Value is not given. Its Bullet Impact Value is 51. Its color is gray.