Magnesium hydride sensitized emulsion explosives can effectively reduce “pressure desensitization” problems that traditional emulsion explosives encounter in utilization. Shockwave desensitization experiments and underwater explosion experiments show that, compared with traditional glass microspheres (GM) sensitized emulsion explosives, magnesium hydride sensitized emulsion explosives are better at resisting pressure desensitization. The microstructures of GM and magnesium hydride sensitized emulsion explosives before and after compression are studied with scanning electron microscopy, and the pressure desensitization resisting mechanism of magnesium hydride sensitized emulsion explosives is discussed. This work shows that reduction of “hotspots” is the key factor of pressure desensitization of emulsion explosives through comparative research.

Aiming to solve the problems caused by primary explosives in traditional detonators, a new kind of non‐primary explosive detonator based on the principle of flying plate detonator is invented. However, in some special circumstances, such as high temperature, strong radiation, strong magnetic field, overload, high‐pressure conditions, the non‐primary explosive detonator cannot work well because of the defects of its usual used initiating method like electric hot wire initiating devices, electric exploding bridge wire initiator, and initiating by a shock‐conducting tube. In this context, initiation by low energy laser is applied to non‐primary explosive detonator. After this combination, the non‐primary explosive detonator performs well in resisting high temperature, high pressure, overload, and electric interference.

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Due to the inefficiency problem of the cut blasting in rock excavation and rock breaking, a shell radial shaped charge device was proposed based of the ideal of ‘cutting to slotting’ and it was validated through experiments. For this device, the shell materials are used to be shaped materials and multiple shaped ring is designed on the circular tube. It can not only reduce charge quantity but also raise the utilization ratio of explosive energy. After explosion, multiple radial shaped charge jets can be formed along the axial line in sequence and then the surrounding rock mass would be cracked. The crack network will be formed along with the further extension of the fraction under the action of quasi static loading of detonation gas. The shell radial shaped charge device was tested through the cut blasting model experiment. Experimental results show that the utilization ratio of blasting hole nearly approaches 98% with this device. The blasting efficiency and cyclical footage can be improved effectively and the cost of drifting can also be reduced.

In order to improve the effect of explosive hardening and reduce the production cost, the elastic-plastic explosive which consists of RDX, rubber, deterrent, antioxidant and plasticizer was prepared. The experiments including density testing, detonation performance, detonation velocity testing, impact sensitivity, and explosive hardening were carried out. The results show that the density of the elastic-plastic explosive is 1.46g/cm3, the detonation velocity is 6670m/s, the impact sensitivity is 28% and the elastic-plastic explosive can be detonated reliably by a detonator. The explosion hardening on Hadfield steel makes the hardness increased from 187HB to 362HB, which increases by 93.5%.