An experimental assessment of friction effects in the split Hopkinson pressure bar using the ring compression test

Hartley, R.S.; Cloete, T.J.; Nurick, G.N.

doi:10.1016/j.ijimpeng.2006.09.003

Cited by 69 publications

(42 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…If there is excessive friction, a barreling effect is observed, causing stress inhomogeneity and an increase in the measured specimen strength: such tests are not valid for the measurement of bulk properties of a material. Studies of different lubricants [47,92,93] have shown that paraffin wax, petroleum jelly, and molybdenum disulfide grease provide adequate lubrication for high strain rate experiments.…”

Section: Dynamic Loading: Split Hopkinson Pressure Barmentioning

confidence: 99%

High Strain Rate Mechanics of Polymers: A Review

Siviour

Jordan

2016

J. dynamic behavior mater.

286

121

View full text Add to dashboard Cite

The mechanical properties of polymers are becoming increasingly important as they are used in structural applications, both on their own and as matrix materials for composites. It has long been known that these mechanical properties are dependent on strain rate, temperature, and pressure. In this paper, the methods for dynamic loading of polymers will be briefly reviewed. The high strain rate mechanical properties of several classes of polymers, i.e. glassy and rubbery amorphous polymers and semi-crystalline polymers will be reviewed. Additionally, time-temperature superposition for rate dependent large strain properties and pressure dependence in polymers will be discussed. Constitutive modeling and shock properties of polymers will not be discussed in this review.

show abstract

Section: Dynamic Loading: Split Hopkinson Pressure Barmentioning

confidence: 99%

High Strain Rate Mechanics of Polymers: A Review

Siviour

Jordan

2016

J. dynamic behavior mater.

286

121

View full text Add to dashboard Cite

show abstract

“…Many previous studies have been performed on this subject (Li and Meng 2003;Hartley et al 2007;Iwamoto and Yokoyama 2012). To examine this influence on the particle model, numerical dynamic tests were conducted on model D under different friction coefficients varying from l = 0.0 to l = 0.7, and the results are shown in Fig.…”

Section: Effects Of Frictionmentioning

confidence: 99%

Numerical Simulation of the Rock SHPB Test with a Special Shape Striker Based on the Discrete Element Method

2013

View full text Add to dashboard Cite

A split Hopkinson pressure bar (SHPB) system with a special shape striker has been suggested as the test method by the International Society for Rock Mechanics (ISRM) to determine the dynamic characteristics of rock materials. In order to further verify this testing technique and microscopically reveal the dynamic responses of specimens in SHPB tests, a numerical SHPB test system was established based on particle flow code (PFC). Numerical dynamic tests under different impact velocities were conducted. Investigation of the stresses at the ends of a specimen showed that the specimen could reach stress equilibrium after several wave reverberations, and this balance could be maintained well for a certain time period after the peak stress. In addition, analyses of the reflected waves showed that there was a clear relationship between the variation of the reflected wave and the stress equilibrium state in the specimen, and the turning point of the reflected wave corresponded well with the peak stress in the specimen. Furthermore, the reflected waves can be classified into three types according to their patterns. Under certain impact velocities, the specimen deforms at a constant strain rate during the whole loading process. Finally, the influence of the micro-strength ratio (s c =r c ) and distribution pattern on the dynamic increase factor (DIF) of the strength DIF were studied, and the lateral inertia confinement and heterogeneity were found to be two important factors causing the strain rate effect for rock materials.Keywords SHPB Á Special shape striker Á Discrete element method Á Strain rate effect Micro-strength ratio (ratio of contact-bond shear to normal strength) n Time-step N Current time-step DTðnÞ Interval time under time-step n(s) l Frictional coefficient at the specimen/bar interface

show abstract

“…This constraint generates a hydrostatic stress that is superimposed upon the axial stress, resulting in a three dimensional stress state. For this reason, the measured mechanical response of tested materials tends to exaggerate their real behavior [39]. Moreover, this error is more evident for thin specimens which results in high measured yield stresses [35].…”

Section: Assumption Of Split Hopkinson Pressure Barmentioning

confidence: 99%

“…Friction is considered to be the largest source of error in the SHPB technique [39]. During high strain rate compression tests, friction between the surfaces of the sample and the bars tends to constrain the lateral flow of the sample.…”

Section: Assumption Of Split Hopkinson Pressure Barmentioning

confidence: 99%

Specimen Geometry Effect on the Deformation Mechanisms of Polypropylene-Based Composites Under Impact Loading at Different Temperatures

Wang

Bahlouli

Boumbimba³

et al. 2016

J. dynamic behavior mater.

View full text Add to dashboard Cite

Dynamic behaviors of polypropylene (PP), PPethylene propylene rubber (PP-EPR) and PP-nanoclay (PP-Nanocor) composites were studied by using split Hopkinson pressure bar at different temperatures and under different strain rates. Samples with two different geometries and with or without petroleum jelly lubricant were tested under identical testing conditions to compare the dynamic responses with underlying deformation mechanisms. For all the test temperatures and strain rates, the dynamic responses of neat PP and PP-Nanocor showed post-yield strain-softening, whereas those of PP-EPR showed strain-hardening after the yield point. PP-Nanocor showed more strain-softening compared with neat PP at room temperature due to the more important localized shearing deformation at the nanofiller/matrix interfaces. Friction between the sample and the bars affected the dynamic response of the materials at room temperature as well as high temperatures seen as differences in behavior between the dynamic behaviors of the non-lubricated thin samples and the non-lubricated thick samples under the same testing conditions. At room temperature and without lubrication, the thicker specimens of neat PP and PPNanocor failed during dynamic testing due to the barrelinginduced crack that propagated in the specimen and led to the formation of a peripheral fragment. Although petroleum jelly provided a satisfactory lubrication condition for both neat PP and PP-based composites at room temperature and at high temperatures, by reducing the friction effect on the yield behavior, the lubrication did not have a significant effect on the post-yield behavior of neat PP and PPNanocor, particularly for the room temperature testing and with the thick specimens.

show abstract

An experimental assessment of friction effects in the split Hopkinson pressure bar using the ring compression test

Cited by 69 publications

References 19 publications

High Strain Rate Mechanics of Polymers: A Review

High Strain Rate Mechanics of Polymers: A Review

Numerical Simulation of the Rock SHPB Test with a Special Shape Striker Based on the Discrete Element Method

Specimen Geometry Effect on the Deformation Mechanisms of Polypropylene-Based Composites Under Impact Loading at Different Temperatures

Contact Info

Product

Resources

About