添加剂对黑索今颗粒包覆度和机械感度的影响

采用接触角测定仪测定了添加不同助剂的黏结剂溶液表面张力，以及在RDX炸药颗粒表面的接触角，通过扫描电镜图像、X射线能谱和样品的机械感度评价样品的表面包覆情况。分析了铺展系数、黏附功与包覆度、特性落高的关系，发现包覆度随铺展系数的增大而增大，随黏附功的增大而减小，说明铺展系数越大、黏附功越小，对润湿包覆越有利。且包覆度越大，特性落高越大，机械感度越低。扫描电镜研究结果表明，包覆后样品表面有一层均匀的橡胶薄膜。XPS分析结果表明，未添加助剂时的包覆度为16.85%，添加增黏剂和表面活性剂后样品包覆度可提高到95.41%。机械感度结果也表明，添加合适的助剂后特性落高由11.47 cm提高到25.12 cm，摩擦感度也明显降低。

Influence of additives on the coverage degree and mechanical sensitivity of RDX

The surface tension of binder containing different additives and the contact angle with RDX were measured by a contact angle meter. The coating quality is evaluated according to the micro-images acquired by scanning electron microscopy (SEM), the spectrum by X-ray photoelectron spectroscopy (XPS) and the impact sensitivity of the samples. The spreading coefficient (S) and adhesive work (W₁₂) were calculated, and then the dependence of the coverage degree (R) on S and W₁₂ were analyzed. The results show that R increased with the increase of S, and reduced with the increase of W₁₂. It indicates that the better coating quality comes with the bigger S and the smaller W₁₂. And the lower mechanical sensitivity comes with the greater coverge degree. The results of SEM show that a thin layer of film was formed on the surface of RDX. The results of XPS show that the additives can raise the coverage degree from 16.85% to 95.41%. The results of impact sensitivity show that the additives can raise the characteristic fall distance from 11.47 cm to 25.12 cm, and significantly reduce friction sensitivity.