Compaction of Non-Consolidated HMX Beds

摘要

We present experimental data for the hydrostatic compaction to 50 MPa of non-consolidated beds of HMX. The starting material consists of the standard Class A, Class D, and Class E specifications, as well as the sieve cuts at 100 to 125 and 425 to 500 microns. We measure the hydrostatic pressure-volume relation for each sample along a loading and unloading path to 10, 30, or 50 MPa, then recover the sample in the last three sizes to obtain the final particle size distribution. The experiments are made using a classic bellows piezometer technique, with pressurization rates of about 0.1 MPa/s at room temperature. The P-v data support the classical picture of compaction of non-consolidated beds, in which particles move and rotate to fill voids at low external stress. At higher stresses, the compaction behavior is a function of the particle size distribution. For monomodal distributions, there is extensive fracture of the mode size, followed by fracture of the sizes best able to fit into voids created by the mode size. For multimodal distributions, this mechanism is not present to as large an extent, with agglomeration being the dominant behavior in Class E compaction. We find about a 2% sample-to-sample variation in the relative density. Measurable differences in the P-v curves of all size distributions below about 75% TMD become small at higher relative densities. The details of the low pressure curves depend most strongly on the initial particle packing and the type of size distribution (mono- or multi-modal). 23 refs., 12 figs., 1 tab. (ERA citation 12:025362)