【摘要】 目的研究身管径向精密锻造中,不同变形阶段的锻造比与塑性应变的关系,以及内膛成形的条件。方法提出了局部锻造比的概念,推导了整体锻造比和局部锻造比的关系。基于局部锻造比,给出了单次锻打所产生的塑性应变增量,求出了径向锻造过程的全场塑性应变的解析解。将弹线膛同时锻造成形的过程分为下沉段和锻造段,探讨了下沉段和锻造段的锻造比对各自塑性变形的影响,提出了内膛成形的必要条件,并用实际身管锻打进行了试验验证。结果每个截面沿轴向的变形都是均匀的拉应变,其值和锻造比成正比;径向和周向应变随着径向位置而变化,且和半径的平方成反比。结论下沉段的锻造比过大对内膛成形不利,增大锻造段的锻造比有利于内膛的成形。更多还原

【Abstract】 Objective To study the relation of plastic strain and forging ratios in different deformation stages and the requirements for bore forming in the process of radial precise forging of barrel. Methods The concept of local forging ratio was proposed,and the relationship of local and whole forging ratios was derived. The increment strain of single forging was derived from whole forging ratio,and the whole strains of radial forging were obtained. The sinking stage and forging stage were proposed in the radial forging process of a barrel’s bore,and the effects of their forging ratios on plastic strain were studied. The requirement of bore forming was proposed,and the actual example of forging was used to proved the requirement. Results The calculation results indicated that the axial strain was uniform tension strain and was proportional to the forging ratio; the radial and circumferential strains changed with the radial position and were inverse proportional to the square of forging ratio. Conclusion Too large a forging ratio of sinking stage is bad for bore’s forming and a large forging ratio of forging stage is good for bore forming.更多还原