Plastic instability in uni-axially anisotropic (<i>r</i> value) materials

Plane Strain Slip Line Theory for Anisotropic Rigid/plastic Materials

A SLIP line theory governing states of incipient plane flow at the yield point load is developed for anisotropic rigid/plastic materials which exhibit a reduced yield criterion, governing states of plane flow, that depends only on the deviatoric parts of the in-plane stress tensor. It is shown that every homogeneous, incompressible material which complies with the principle of maximum plastic w...

Prediction of Instability in Planar Anisotropic Sheet Metal Forming Processes

In this paper instability of planar anisotropic sheet metal during a few forming processes is investigated for the first time. For this reason components of the constitutive tangent tensor for planar anisotropic sheets are developed. By using the above tensor location of necking is predicted. Direction of the shear band is also predicted using the acoustic tensor. A finite element program is pr...

Superfluid Phase Stability of He in Axially Anisotropic Aerogel

Measurements of superfluid He in 98% aerogel demonstrate the existence of a metastable A-like phase and a stable B-like phase. It has been suggested that the relative stability of these two phases is controlled by anisotropic quasiparticle scattering in the aerogel. Anisotropic scattering produced by axial compression of the aerogel has been predicted to stabilize the axial state of superfluid ...

Fiber reinforced plastic composites using recycled materials

This work investigates the feasibility of using recycled high density polyethylene (rHDPE), recycled polypropylene (rPP) and old newsprint fiber (ONP) to manufacture fiber reinforced composites. The boards were made through air-forming and hot press. The effects of the fiber loading and coupling agent content on tensile, flexural, internal bond properties and water absorption and thickness swel...

14 Lightweight Plastic Materials