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An ultrafine-grained (UFG) pure zirconium(Zr) refined by compounding with a size of Φ4×6 mm was subjected to a unidirectional compression test using a Gellble-3800 thermal simulation tester at the temperature of 300°C-450°C and a strain rate range of 0.001-0.05 s −1 . Experimental results showed that the flow stress of UFG pure Zr refined by compounding is highly sensitive to temperature and strain rate, and the peak stress decreases with increase in deformation temperature and increases with increase in strain rate. The Arrhenius constitutive equation based on the experimental data can effectively predict peak stress in actual thermal deformation, The correlation coefficient between the actual value and the predicted value can reach as high as 0.99722. With the increase in deformation temperature and the decrease in strain rate, the UFG pure Zr refined by compounding otably undergoes dynamic recovery and dynamic recrystallization. These findings are based on the hot processing map and microstructure characteristics of UFG pure Zr refined by compounding. The optimal hot-working windows are determined to be in the deformation temperature of 320°C-360°C with strain rate of 0.005-0.01 s −1 and the deformation temperature of 410-450°C with strain rate of 0.003-0.01 s −1 .

Roll straightening is an important process link in sheet production. Due to the step change of the straightening force during the straightening bite and the tail flick, the whole-plate length straightening and pressing process changes will affect the straightening effect. Based on the solution of the curvature integral straightening process, this paper introduces the stiffness coefficient of the straightening equipment. Through C language programming, the iterative solution has been realized, and the process parameters of the dynamic change of the straightening reduction have been obtained. The enumeration method was used to establish a calculation method to optimize the entire board-length straightening process. The laboratory comparison of the 11-roll straightening machine proves that the straightening process optimization model meets the application requirements.

To obtain a compatible material with good wear resistance (WR) and toughness, a composite material with high‐chromium cast iron (HCCI) dispersed in low‐carbon steel (LCS) is prepared through multilayer hot rolling. The microstructure and mechanical properties of the composite are investigated. The macrostructure of the composite material reveals that the HCCI layers are necked, fractured, and dispersed in LCS after hot rolling. The two materials combine well without unconnected areas and macrovoids on the interface; however, broken oxides are observed at the interface. Decarburization occurs at the LCS side near the interface and a 15−20 μm‐wide ferrite zone is formed at the LCS side. Fe, Cr, Mn, and C elements diffuse at the interface. A pearlite band is formed at the interface, and the thickness of the diffusion is about 2−4 μm. Due to the addition of ductile LCS, the impact toughness of the composite material is about 2.5 times higher than that of the as‐cast HCCI, whereas the WR of the composite material is lower than that of HCCI (about 16%). The dispersed HCCI in the composite produces a shadow effect during the sliding wear, which provides protection and support for LCS.

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