Pressure-shear experiments on granular materials.

Reinhart, William Dodd (Sandia National Laboratories, Albuquerque, NM) ; Thornhill, Tom Finley, III (, Sandia National Laboratories, Albuquerque, NM) ; Vogler, Tracy John ; Alexander, C. Scott (Sandia National Laboratories, Albuquerque, NM)

Sandia National Laboratories

关键词: Stresses;    Fractures;    Tungsten Carbides;    36 Materials Science;    Comminution;   

DOI  :  10.2172/1030312
RP-ID  :  SAND2011-6700
RP-ID  :  AC04-94AL85000
RP-ID  :  1030312

美国|英语

来源: UNT Digital Library

【 摘 要 】

Pressure-shear experiments were performed on granular tungsten carbide and sand using a newly-refurbished slotted barrel gun. The sample is a thin layer of the granular material sandwiched between driver and anvil plates that remain elastic. Because of the obliquity, impact generates both a longitudinal wave, which compresses the sample, and a shear wave that probes the strength of the sample. Laser velocity interferometry is employed to measure the velocity history of the free surface of the anvil. Since the driver and anvil remain elastic, analysis of the results is, in principal, straightforward. Experiments were performed at pressures up to nearly 2 GPa using titanium plates and at higher pressure using zirconium plates. Those done with the titanium plates produced values of shear stress of 0.1-0.2 GPa, with the value increasing with pressure. On the other hand, those experiments conducted with zirconia anvils display results that may be related to slipping at an interface and shear stresses mostly at 0.1 GPa or less. Recovered samples display much greater particle fracture than is observed in planar loading, suggesting that shearing is a very effective mechanism for comminution of the grains.