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在200—300毫米輥径的横軋机上于不同溫度、速度、变形程度、变形区长度与直径之比以及外端等条件下,用金相法和硬度法对各鋼种的圓棒的变形分布和中心破裂进行了研究。在冲床上用端面画有同心圓的鋁棒和鉛棒进行了常溫的旋轉橫鍛試驗,以了解横鍛横軋时金属的变形分布。試驗結果表明: 1.一次横鍛时,表面层的变形最大,越靠中心变形愈小。当压縮率不大时,中心处可能只发生弹性变形。2.旋轉橫鍛时,表面层和中心区的塑性变形較大,过渡区的变形最小。当变形率很小时,塑性变形亦可能不致于深入到中心区。3.横軋时金属的变形規律与旋轉橫鍛时相似,但在压縮很小时,断面中心只发生弹性变形。4.横軋时,軋制溫度、軋制速度增高,压縮率及变形长度与直径比越大,外端越小,中心破裂愈易产生。
In the 200-300 mm diameter of the cross-rolling mill at different temperatures, speeds, degrees of deformation, deformation zone length to diameter ratio and the outer end of the other conditions, the use of metallographic and hardness method for each type of steel bar deformation distribution and Center rupture was studied. In the press with the end face drawn concentric aluminum rods and lead rods were carried out at room temperature rotary cross-forging test to understand the transverse cross-rolling metal deformation distribution. The test results show that: 1. A cross-forging, the deformation of the surface layer maximum, the more the center of deformation smaller. When the compression ratio is not large, the center may only be elastic deformation. 2. When rotating transverse forging, the plastic deformation of the surface layer and the center area is larger, and the deformation of the transition area is the smallest. When the deformation rate is small, plastic deformation may not be due to deep into the central area. The deformation law of the metal during the cross-rolling is similar to that during the rotary cross-swaging. However, when the compression is small, only the elastic deformation occurs at the center of the cross-section. 4. Cross-rolling, the rolling temperature, rolling speed increased, the compression ratio and deformation length and diameter greater, the smaller the outer end, the more likely to produce the center of rupture.