A comprehensive computer based system for online prediction of mechanical properties and offline prediction of the microstructure of hot rolled C-Mn and microalloyed steel strip of has been developed. The approach used was based on two types of model: a neural model that predicts the mechanical properties and a physically based semiempirical model that predicts the microstructural features. The mechanical properties of the hot rolled strip are calculated online, but it is also possible to simulate the effects of steel composition and process parameters on the mechanical properties. The microstructural model is an offline tool for use in research and development, product planning and production. It can be applied to the study of microstructural evolution during hot rolling or to estimate changes caused by process conditions or by the steel composition. The system provides information that has not been available before, thus enabling more precise process planning, improvement of the consistency of products and better opportunities for future steel development.

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Low density and poor mechanical performance often limit utilisation of sawn wood from fast-growing plantation forests. Thermo-hygro-mechanical modification (THM) of timber is one innovation for improving the properties of light-weight wood species. The objective of this study was to determine the effects of THM and subsequent thermal treatment on dry density, modulus of elasticity (MOE), compression strength, Brinell hardness, and swelling behaviour in immersion tests on two fast-growing Vietnamese species, acacia (Acacia mangium) and rubberwood (Hevea brasiliensis). Test boards were modified in an industrial kiln, in which a tangential thickness compression of 14% and 12% were aimed for acacia and rubberwood, respectively, either with or without subsequent thermal treatment at 210 °C. Dry density, MOE, Brinell hardness, compression strength, and dimensional changes in water immersion tests of specimens were measured from the modified and unmodified reference materials, the latter ones being kiln dried at 50 °C. The results showed that the responses of the mechanical properties were more evident for rubberwood than for acacia. In rubberwood, the MOE and compression strength of wood thermo-hygro-mechanically modified with or without thermal treatment were higher than those of kiln-dried reference specimens throughout the thickness profile. In case of acacia, similar differences between the modified and reference specimens were observed only in the surface layer. Density and Brinell hardness of thermo-hygro-mechanically modified rubberwood were higher than those of reference specimens, but after thermal treatment they did not differ from (acacia) or were lower (rubberwood) than those of THM specimens. Post-compression thermal treatment increased the hydrophobicity of THM specimens.

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