it is well-known that severe deformation to metals causes a direct grain refinement of the matrix without special heat-treatments due to the mechanism of dynamic continuous recrystallization (dcr). however, the microstructural revolution during severe deformation is seemed to be different depending on the deformation mode, namely the direction of deformation. in general, multi-directional defor...

It is well-known that severe deformation to metals causes a direct grain refinement of the matrix without special heat-treatments due to the mechanism of dynamic continuous recrystallization (DCR). However, the microstructural revolution during severe deformation is seemed to be different depending on the deformation mode, namely the direction of deformation. In general, multi-directional defor...

It has been clarified that deformation and annealing of martensite starting structure can produce ultrafine-grained structure in low carbon steel.  This study aims to investigate the texture evolution and mechanical properties of samples with martensite structure deformed by two different forging processes. The martensitic steel samples were forged by plane strain compression and multi-directio...

We give error estimates for the approximation of a laminated microstructure which minimizes the energy R (rv(x))dx for a rotationally invariant, double well energy density (A). We present error estimates for the convergence of the deformation in L; the convergence of directional derivatives of the deformation in the \twin planes," the weak convergence of the deformation gradient, the convergenc...

Martensitic crystals which can undergo a cubic to tetragonal phase transformation have a nonconvex energy density with three symmetry-related, rotationally invariant energy wells. We give estimates for the numerical approximation of a first-order laminate for such martensitic crystals. We give bounds for the L2 convergence of directional derivatives in the “twin” plane, for the L2 convergence o...

An object-oriented approach to the analysis and design of metal forming and directional solidi cation processes is presented. A number of speci c ideas are introduced on how a deformation or a solidi cation process can be partitioned into subproblems that can be independently developed and tested in the form of class hierarchies. Class development based on mathematical and/or physical arguments...

The deformation of a directionally solidified columnar dendritic mushy zone in a transparent succinonitrile-acetone (SCN-ACE) alloy has been studied experimentally. In addition to solidifying dendritically like a metal alloy, this alloy also has mechanical properties that are similar to those of metals near the melting point. The experiments are relevant, for example, to the deformation of a pa...

Non-trivial deformations result in local contractions and expansions. These naturally capture object scalings but can have a negative side effect, namely making object features disappear or inflate. For this reason we want the deformation fields to have zero acceleration in the direction perpendicular to image features; this guarantees that the features are only ‘transported’. This requirement ...