摘要
利用对数应变的可加性和体积可压缩材料的塑性方程,建立了大型锻件中疏松孔隙率与应力和变形的解析关系式,进而得到疏松压实条件。应力和应变状态对疏松压实有各自不可替代的作用。静水应力的存在是疏松压实的必要条件。压实过程初期,静水应力起主要作用,压实过程后期,变形起减小应力值的作用。利用铅质疏松材料的压实试验,检验了疏松材料中孔隙率与应力、变形的关系,表明所得的疏松压实条件可作为实际生产的参考依据。
Based on the logarithmic strain's principle of superposition and volume compressible material's plastic function, the analytic formulas for large forging porosity and cavity ratio, stress and deformation are established . Then the porosity collapse factor is given. Through the discussion of the relationship between porous material's cavity ratio and stress, deformation, it can be concluded that stress state and strain state play an irreplaceable role in porosity collapse process. The existence of hydrostatic stress is the prerequisite of porosity collapse process. At the beginning of the collapse process, hydrostatic stress plays an important role, and at the end of the collapse process, deformation takes the function of reducing stress value. An experiment is also carried out using lead porous material. The result shows the porosity collapse factor given can be well used in real production for reference.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2003年第3期126-129,共4页
Journal of Mechanical Engineering
基金
教育部博士点基金资助项目(97021606)。
关键词
材料加工
塑性力学
塑性成形
大椴件
Material processing Plastic mechanics Plastic deformation Large forging
