Abstract In recent years, considerable research has been devoted to the development of ultrafine-grained (UFG) structural metals fabricated by various severe plastic deformation (SPD) techniques. Among these techniques, differential speed rolling (DSR) has been considered as the continuous forming method in which bulk sheet materials pass through two identical rolls with different speeds of the rolls, effectively imposing intense plastic strain based on shear deformation. This review describes the principles of the DSR process, including the strain imposed by DSR, processing routes, and macro-shear characteristics associated with the processing routes; it also outlines the processing factors that affect grain refinement, such as total thickness reduction, thickness reduction per pass, rolling speed, roll speed ratio, number of operations, and rolling temperature. The essential features of the resultant microstructural variables, including the grain size and morphology, grain boundaries, deformation textures, and dislocation density developed in materials with HCP, FCC, and BCC crystals deformed by the DSR process are also summarized. In addition, the structural properties of metals subjected to DSR are reviewed, including strength, hardness, and ductility at room and elevated temperatures.

中文翻译：

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用于金属晶粒细化的连续差速轧制：加工、微观结构和性能

摘要 近年来，大量研究致力于通过各种严重塑性变形（SPD）技术制造的超细晶（UFG）结构金属的开发。在这些技术中，差速轧制 (DSR) 被认为是一种连续成型方法，在这种方法中，块状板材以不同的速度通过两个相同的辊，有效地施加基于剪切变形的强烈塑性应变。本综述描述了 DSR 工艺的原理，包括 DSR 施加的应变、加工路线以及与加工路线相关的宏观剪切特性；它还概述了影响晶粒细化的加工因素，例如总厚度减少量、每道次厚度减少量、轧制速度、辊速比、操作次数、和轧制温度。还总结了所得微观结构变量的基本特征，包括晶粒尺寸和形态、晶界、变形纹理和位错密度，这些材料在具有通过 DSR 工艺变形的 HCP、FCC 和 BCC 晶体的材料中产生。此外，还审查了经受 DSR 的金属的结构特性，包括室温和高温下的强度、硬度和延展性。