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In order to optimize the hot deformation processing, useful and efficient mathematical models able to evaluate the different aspects of the response of plain carbon steel to hot plastic deformation are among the most important prerequisites. In this paper, a group of mathematical equations were developed according to a series of experiments data to model the austenite grain evolution, static and dynamic recrystallization during-deformation and post-deformation of plain carbon steel. And then those equations were implemented into ABAQUS6.5 (License Agreement Identifier: 27SHANU) using the VUMAT for numerical simulations of cylinder specimen compression.

In hot metal forming processes, the material is subjected to the thermo-mechanical processing. A fully three dimensional thermo-mechanically coupled FEM-simulation of an eleven pass hot rough rolling process of H-beam has been performed. Microstructure evolution equations available in literatures were incorporated into the commercial FE solver ABAQUS/Explicit, through user defined subroutine VUMAT, to simulate the microstructure evolution. Since it’s impractical to obtain the austenite grain size distribution in the beam blank during industrial hot rolling, the calculated rolling loads are compared with the mills loads instead of grain size comparison between the predicted average value and the real ones.

Strain ZSI isolated from heavy metal contaminated soil was identified by morphological observation and 16S rDNA sequence analysis. The tolerance to heavy metals and 12 antibiotics was examined. The results showed that the strain was most homophylic with Cupriavidus sp. It has high tolerance to serval metals, and the order was Cu＞Zn＞Cd＞Ni＞Mn=Co＞Pb. The strain can resistant to 9 antibiotics.

Hot rolling is a basic metal forming technique that is used to transform preformed shape into final products of forms more suitable for further processing. As the hot stock progresses through the forming surfaces, the shape eventually reaches a constant state. With the assumption of forming process has reached steady-state condition, a simulation technique based on elements re-meshes has been constructed to analyze the H-beam metal hot roll process. The technique includes the following approaches: the solution was halted as soon as the steady-state criteria were met, and the plane of elements, which first satisfied the steady-state criteria were written to database, SSES for short; a two-dimensional model was created to model the hot stock cooling between the two roll passes and a geometric part was generated and meshed with quadrilateral elements to transfer the nodes temperatures; a new three-dimensional model extruded from the two-dimensional model was constructed to model the next roll pass with the transfer of nodes temperatures and element integration points equivalent plastic strain(PEEQ), identifying the plastic deformation extent for the classical metal plasticity models, from the new two-dimensional model and the first three-dimensional model respectively. Gleeble-1500 tester is used to get the true stress and true plastic strain data for modeling the yield behavior of material Q235. The effectiveness of the simulation technique has been proved by a simulation of 11-pass H-beam rolling process.