The tensile mechanical behaviors of 1 6Si 1 58Mn 0 19C TRIP steels under high strain rate were studied with a self designed pneumatically actuating tensile impact bar bar tester,and compared to the quasi static tensile behavior.
The experiments on Kevlar49 fibre bundles under quasi static tension and tensile impact were performed in MTS810 and Bar Bar Tensile Impact Apparatus, respectively. The stress strain curves of Kevlar49 fibre bundles were obtained at strain rates ranging from 10 -4 /s to 10 3/s.
In this paper,using our design of bar bar tensile impact apparatus,we performed an experimental study of ARALL and ARALL(prestress)in the strain rate range from 200s -1 to 1300s -1 .The complete stress strain curves of composite under tensile impact was obtained.
Tensile impact test of a unidirectional Kevlar 49/phenolic composite(KFRP)were carried out in a Bar Bar Tensile Impact Apparatus. Three high strain rates 150s 1 ,400s -1 and 1500s -1 were used in the experiments; complete stress strain relations have been obtained respectively.
In this paper,the Fourier method and corresponding code (FFTDSP) for dispersion analysis in the bar is applied to the Split Hopkinson Pressure Testing System and the Bar Bar Tensile Impact Testing System.
Tensile impact tests of aramid (Twaron) fiber bundles are carried out under high strain rates with a wider range of 0 001~1000 s -1 by means of MTS and bar bar tensile impact apparatus.
Cracks may occur in the centre of the remainder of a billet during bar- bar combined extrusion if the original height or the remaining height of the billet is short.In this paper,the upper bound method is used to determine the conditions for the formation of central cracking by establishing a kinem- atically admissible velocity field with crack defects and utilizing the minim- um energy principle.The experimental results showed that the increase of de- formation will cause the critical relative ...
The papers using upper-bound approach to analyze the forming processesare fairly numerous [1-5, 7-12], however, bar-bar combined extrusion has al-most not been studied systematically up to the present time. A theoreticalwork on axisymmetric bar-bar combined extrusion was presented by Yang etal. [3], who introduced the arbitrarily inclined triangular elements for velocityfield and derived the upper-bound loads on the punch, but it is only appli-cable to the final stage of the process ...
The bar-bar tensile impact apparatus was simplified as an axisymmetric linear elastic dynamic system containing several interfaces with physical or geometric discontinuity.Two dimensional finite-difference method and self-designed computing program BBID-Ⅱ were used to obtain the dynamic response of the system. Displacements on the interfaces with physical discontinuity were treated by a new method with two fictitious boundaries.The entire computation scheme was justified by several numerical eaa...