Microstructure and Energy Release Characteristics of W-Ni-Al All-metal Energetic Structural Materials Prepared by Explosive Sintering

Energetic structural materials (ESMs) have been widely studied due to their potential applications in the military field as reactive fragments, casings and shaped charges. Among them, Ni-Al ESMs, as typical intermetallic ESMs, face limitations in application due to their low density. Based on the explosive sintering method, the high-density W-Ni-Al ESMs is prepared by adding tungsten. A sample with a molar ratio of 1:1:1 is prepared, achieving a density of 10.08g/cm³ (theoretical density of 97.6). The microstructure of the sample is characterized using scanning electron microscopy, X-ray diffraction, and transmission electron microscopy. The thermal reaction properties of W-Ni-Al ESMs in air and argon are systematically investigated by differential scanning calorimetry and thermogravimetric analysis. The impact-induced energy release behaviors of W-Ni-Al ESMs are studied through ballistic gun experiments. Results show that the W-Ni-Al ESMs obtained via explosive sintering have a uniform microstructure, free of cracks and intermetallic phases. Under two different atmospheres, tungsten does not participate in the intermetallic reaction during heating. The energy release of W-Ni-Al ESMs is primarily attributed to Ni-Al intermetallic reactions at the impact velocities ranging from 765 to 1280m/s.