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Corrugated rolling is one of the metal forming processes using corrugated rolls to machine hard-to-deform metals, which leads to problems of high friction and severe wear. Lubricants are essential to reduce rolling forces, extend the life of corrugated rolls, and improve efficiency. In this work, a comparison of the surface quality of copper plates after corrugated rolling adopting different lubrication conditions (dry condition, O/W lubricant, TiO2 water-based nanolubricants) was made to explore the tribological behavior and lubricant mechanism of water-based nanolubricant during the corrugated rolling of copper plates. The results show that the 3.0 wt.% water-based nanolubricant exhibits excellent lubrication performance, and the maximum rolling force is reduced by 21.49% compared with the dry condition. Additionally, the effect of reduction on the surface quality of corrugated rolled copper plates was explored. The surface roughness at the peak position of the copper plate increased gradually with increasing reduction, and the surface roughness at the trough position showed little change, which was mainly caused by the synergistic effect of the roughness transfer and the high-strain hardening at the trough position of the copper plate. Overall, an optimal concentration of 3.0 wt.% water-based nanolubricant exhibits the best properties in terms of reducing the rolling forces and improving the surface quality of the rolled copper plates during corrugated rolling processes. [ABSTRACT FROM AUTHOR]

During past decades, water-based and oil-in-water (O/W) based nanolubricants with nanoparticles (NPs) as additives have been developed to replace conventional oil-based lubricants for solving contamination problems during rolling processes. The formulations of nanolubricants for rolling need to be continuously improved to provide better lubrication performance. This article reviews the formulation, physicochemical properties, and lubrication mechanisms during rolling with water-based and O/W based nanolubricants, and the effects of nanolubricants on rolling force, surface roughness and oxide skin formation during rolling are discussed. This review aims to facilitate the fundamental understanding of nanolubrication and the development of rolling lubrication technology. [ABSTRACT FROM AUTHOR]

In this study, the effect of cold rolling reduction ratio (CRRR) on the microstructure and mechanical properties of ferritic stainless steel (FSS) 430 were analyzed based on a series of experiments. The results show that the thickness of coarse grain bands decreases with an increase in CRRR, and when the CRRR increases to a certain value, the coarse grain bands break down into refined, equiaxed grains due to the plastic deformation. In addition, the optimization of CRRR was found to benefit both the microstructural refinement and mechanical properties of FSS 430. Also, the optimization of CRRR optimized the texture structure of FSS 430 by reducing the fraction of undesired components ({110} < 110 > component, for example), giving a rise to the plasticity of material. On the other hand, the formation of Lüders band can also be affected by the modification of CRRR. Overall, an optimal CRRR of 70% was obtained with refined microstructure and texture structure, thereby improving the mechanical properties of FSS 430. [ABSTRACT FROM AUTHOR]

Systematic study on the microstructural evolution and mechanical properties of ferritic stainless steel (FSS) 430 with different annealing processes was carried out in the present work. The results show that microstructural refinement can be achieved by optimization of annealing processes, improving elongation, yield strength, and tensile strength of FSS 430. An optimal annealing temperature of 950 ℃ is found with better homogeneity and enhanced mechanical properties among the cold-rolled and annealed FSSs. During annealing processes, the fraction of high-angle grain boundaries of FSS 430 annealed at 950 ℃ is found to be the highest, indicating that a homogeneous microstructure with high recrystallization rate is formed inside the FSS 430 strips. In addition, high fraction of the hard grains (SF < 0.4) and low fraction of the soft grains are found inside FSS 430 annealed at 950 ℃, improving the plasticity of material. Overall, the optimization of annealing processes benefits the microstructural refinement of FSS and thereby improving the mechanical properties of materials. [ABSTRACT FROM AUTHOR]