Quasi‐Static Compression Properties and Failure of PTFE/Al/W Reactive Materials

Abstract

Quasi-static compression experiments are performed on two kinds of the PTFE/Al/W reactive material specimens, fabricated by means of the cold isostatic pressing but not sintering or the pressing followed by sintering, respectively. The results show that, compared with the pressed specimens, the sintered specimens show higher failure stress and greater fracture toughness. Moreover, the mesoscale failure behaviors are significantly influenced by the sintering technique and the component ratios. There are significantly different bonding and dispersion type of the PTFE matrix between the pressed specimen and the sintered specimen, resulting in the differences of mechanical properties and failure behavior between the two kinds of specimens.

Influence of Rice Husk Ash on the properties of Concrete: a Review

“…Additionally, the slumps of high-strength concrete incorporating RHA with the replacement of 5-20% were higher than that of concrete adding SF with the same dosage. While, when the replacement was 25% and 30%, the result was adverse [52]. According to the above results, incorporating RHA in concrete increases the water demand, decreases the slump of concrete and has a negative influence on the workability of concrete.…”

The Influence of Initial Defects on Impact Ignition of Aluminum/Polytetrafluoroethylene Reactive Material

“…Nevertheless, the sizes of the cracks rise again for the specimens with molding pressure above 100 MPa, and the widest crack can achieve 0.12 mm at the molding pressure of 150 MPa. Xu's previous research declares that the microcracks would be generated in vicinity of the pores due to a concentration of the stress and grow to some places with defects during the compression . After the propagation and coalescence, the microcracks eventually grow into macrocracks.…”

“…However, when the molding pressure increases from 50 to 80 MPa, the growth of elastic modulus of the MSed specimen is very small, which is similar to a plateau. This might be due to the yield of Al at 80 MPa during molding process, difference in the thermal expansion coefficients and the recovery of the plastic deformation between Al particles and PTFE matrix during the sintering process, as well as the bonding degree of the interface . Different from MSed specimens, the elastic modulus of MSed + PIed specimens firstly rises and then decreases with molding pressure, meaning that rising the molding pressure cannot continuously ensure the impact resistance of the material.…”

“…Cai and Herbold found that the PTFE matrix is a key factor in the performance of reactive materials, where the plastic deformation of the material is mainly caused by the deformation of PTFE . Combined with the quasistatic compression experiments, Xu showed the differences of mechanical properties and failure behavior between reactive material fabricated by means of the cold isostatic pressing but not sintering or the pressing followed by sintering, respectively . Moreover, Fang and coworkers first introduced TiH 2 into the Al/PTFE reaction system and studied the mechanical and reaction properties by quasistatic compression and X‐ray diffraction .…”

The Mechanical and Reaction Behavior of PTFE/Al/Fe2O3 under Impact and Quasi-Static Compression

“…They also drew the conclusion that the addition of 30 wt.% of coarse W particles improved the impact strength of the material but led to the increase of reactive activity and the decrease of perfectibility of the reaction. Other scholars also carried out in-depth study of PTFE/Al/W from other perspectives using different techniques including quasi-static and dynamic compression (both drop-weight test and SplitHopkinson Pressure Bar), scanning electron microscopy (SEM), X-ray diffraction (XRD), and differential scanning calorimetry (DSC) [5][6][7][8][9].…”