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The rare molybdenum resources are being increasingly used in heavy industries. In this study, the common unidirectional and cross hot rolling operations, for pure molybdenum plates, were numerically simulated by using MSC. Marc software. An elastic–plastic finite element model was employed, together with the updated Lagrange method, to predict stress and strain fields in the workpiece. The results showed that there was a typical three-dimensional additional compressive stress (σy> σz > σx) in the deformation zone, while strain could be divided into uniaxial compressive strain and biaxial tensile strain (εy > εx > εz). Tensile stress σx increased with the accumulation of reduction and the decrease in friction coefficient at the edge of the width spread. More importantly, the interlaced deformation caused by cross-commutations, which were helpful in repairing the severe anisotropy created by unidirectional hot rolling. The evolution of the temperature field of pure molybdenum plate was investigated. The surface quenching depth of the pure molybdenum plate was about 1/6 H under different initial temperatures and reductions. In addition, the fundamental reason for the nonuniform distribution of stress and strain fields was the joint influence of rolling stress, contact friction, and external resistance. By comparing the theoretical simulation value of the model with the experimental verification data, we found that the model was aligning well with the actual engineering.

Molybdenum has a broad application and good prospect in the field of nuclear energy, aerospace, electronics, etc., due to its high melting point, high hardness, corrosion resistance and other excellent performances. In this paper, an isothermal and isochronous annealing heat treatment, at the temperature of 800–1300 °C for 0.5–2 h, was applied to pure molybdenum (PM) sheets with deformation of 70%, 80%, 90%, and 95%. The initial deformation of the PM sheet was increased from 70% to 95%. After annealing at 900–1200 °C for 1 h, the recrystallized grain size gradually decreased. The Goss texture ({110}) was always present in the pure molybdenum sheet with 95% deformation during heat treatment, but its strength decreased with the increase of the temperature. The copper texture ({112}) deflected to a cubic texture, and its orientation changed from {001} to that of cube texture {110}. With the increase of the temperature, the cubic texture was obtained more easily in the pure molybdenum sheet. The recrystallization nucleation mechanism of the pure molybdenum sheet with 95% deformation was mainly in situ nucleation and orientation nucleation. The Avrami index of the pure molybdenum sheet with 95% deformation was calculated by the JMAK equation and found to be 3.6.