液压致裂法在PBX炸药拉伸强度测试中的适用性

为解决高聚物粘结炸药(Polymer Bonded Explosive,PBX)拉伸强度测试中哑铃直拉法(GJB772A-1997)测试效率不高以及巴西试验测试精度欠佳的问题,基于液压致裂原理自主搭建了测试平台,发展了拉伸强度液压致裂测试方法,实现了PBX炸药的拉伸强度的准确测试。为验证该测试方法的有效性,以某PBX模拟材料哑铃试样为研究对象,在同一发试样中先后进行了标准直拉法和液压致裂法拉伸强度测试实验,并将测试结果进行对比。结果表明,液压致裂法测得的拉伸强度((9.49±0.24)MPa)与直拉法测得的拉伸强度((9.24±0.43)MPa)相对误差仅为2.70%,具有很好的测试精度。液压致裂法可在单发哑铃的残样上获得至少四个有效的拉伸强度数据,相较于直拉法具有测试用量少、测试效率高的特点,且测试稳定性良好,表明该测试方法兼具了哑铃直拉法的高精度和巴西试验的低用量高效率,同时可作为一种原位测试手段广泛运用于配方研制以及结构件不同位置的拉伸强度测试。

Applicability of Hydraulic Fracturing Method in Tensile Strength Test of Polymer Bonded Explosives

In order to solve the problems of low efficiency(direct tension test method (GJB772A-1997)) and poor test accuracy (indirect Brazilian test method) intraditional tensile strength testing of polymer bonded explosive (PBX), we independently established a test plat form based on the hydraulic fracturing method (HFM), developed a novel test method of PBX tensile strength, and achieved accurate testing of PBX tensile strength. To further verify the validity of the test method, the tensile strength of the same PBX dumbbell samples was obtained through direct tension test method and HFM, and the test results were compared. It showed that the relative error between the tensile strength by HFM ((9.49±0.24) MPa) and the tensile strength by direct tension test method ((9.24±0.43) MPa) was only 2.70%, showing the high accuracy. Moreover, the HFM can obtain at least four effective tensile strength data on the on the single dumbbell remnant samples. Compared with the direct tension test method, HFM has the characteristics of less material consumption, high efficiency, and good stability for PBX tensile strength testing. It indicates that the HFM has the advantages of the high accuracy in the direct tension method and high efficiency in the Brazilian test. Therefore, HFM can be widely applied in the in-situ test method for formulation development and tensile strength test of different positions of PBX structural components.