Abstract Cold radial forging is an efficient and high-precision process for producing rotary parts such as axles and gun barrels, etc. 30SiMn2MoVA high strength alloy steel is a kind of fine pearlite steel usually used for moulds and barrels. This work focused on the effect of the cold radial forging on the microstructure, texture evolution and plasticity anisotropy of forged steel tube under different forging reductions. The results suggest that most banded structures that are parallel to the axial direction are developed by the radial forging process. The grains are elongated and refined after forging. The increase of dislocation density with the increase of deformation is the reason for grain refinement. Refined grains and high dislocation lead to high strength. Meanwhile, anisotropy was obvious and was exacerbated by the growth of the forging deformation. The circumferential strength and elongation are inferior to the axial. With the increasing of forging ratios, the α-fiber texture is well developed. The relationship between the volume fraction of texture and plastic strain was built. It can predict the volume fractions of the main texture components in the cold radial forged 30SiMn2MoVA steel tube. The Taylor factors of the main orientations were calculated. The {111} (γ-fiber), {110} , {111} (α-fiber), {114} , {112} and {223} texture components help to enhance the axial yield strength. Comparing the ratio of the axial average Taylor factor and the circumferential average Taylor factor with the yield strength ratio, it is found that yield strength anisotropy is not well predicted only taking into account the crystal texture. The effect of banded structures on the strength should also be considered.

中文翻译：

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径向冷锻30SiMn2MoVA高强合金钢管的显微组织、织构演变及塑性各向异性

摘要 径向冷锻是生产车轴、枪管等旋转零件的一种高效、高精度的工艺。30SiMn2MoVA高强度合金钢是一种常用于模具和枪管的优良珠光体钢。本工作重点研究了径向冷锻对不同锻压下锻钢管组织、织构演变和塑性各向异性的影响。结果表明，大多数平行于轴向的带状组织是由径向锻造过程形成的。锻造后的晶粒被拉长和细化。位错密度随着变形量的增加而增加是晶粒细化的原因。细化晶粒和高位错导致高强度。同时，各向异性很明显，并且随着锻造变形的增长而加剧。周向强度和伸长率不如轴向。随着锻造比的增加，α-纤维织构更加发达。建立了织构体积分数与塑性应变之间的关系。它可以预测冷锻30SiMn2MoVA钢管中主要织构成分的体积分数。计算了主要方向的泰勒因子。{111}（γ-纤维）、{110}、{111}（α-纤维）、{114}、{112} 和{223} 织构成分有助于提高轴向屈服强度。将轴向平均泰勒系数和周向平均泰勒系数的比值与屈服强度比进行比较，发现仅考虑晶体结构不能很好地预测屈服强度各向异性。还应考虑带状结构对强度的影响。