环形件分级扩径成形及开裂研究  

Research on grading expanding process and crack for rings

作　　者：赵艳华[1] 李庆华[1] 李付国[1] 汪程鹏[1] 

机构地区：[1]西北工业大学材料科学与工程学院,陕西西安710072

出　　处：《锻压装备与制造技术》2012年第1期79-83,共5页China Metalforming Equipment & Manufacturing Technology

摘　　要：面对现有环件机械扩径工艺的诸多不足,分级扩径工艺得到了发展和应用。本文介绍了该工艺的基本特点,并以双级扩径工艺为研究对象,从理论上推导了扩径力和扩径行程的计算公式。采用ABAQUS软件对扩径过程进行了模拟,获得了扩径过程中材料参数对锥杆下压力的影响规律,从而验证了理论推导的准确性。为了解决环形件扩径过程中的开裂问题,运用损伤力学的临界空穴扩张比理论,并借助塑性力学方程,建立了环形件的扩径成形无开裂条件,以此作为环件预测开裂的依据,并通过实验证明了该条件的正确性。Aiming at existing insufficient of mechanical expanding for rings, the grading expending process has been developed and applied. The process characteristics have been introduced in the text. Taking double grading process as an object, the calculation formula of expanding force and stroke have been theoretically derived. The expanding process has been simulated by use of software ABAQUS, and the influence law of parameter of material on pressure cone stem in expanding process has been gained, which verifies the accuracy of theoretical derivation. In order to prevent cracking in the process of expanding, the theory of critical void growth ratio in damage mechanics has been applied to establish the condition of expanding forming without cracking with help of plastic mechanics equation. The condition is the criterion for the fracture forecast, which has been verified by experiments.

关 键 词：机械制造 扩径 环件 数值模拟 

分 类 号：TG394[金属学及工艺—金属压力加工]