初始条件对粉末连杆锻造致密过程影响的模拟研究

为研究在不同初始条件(初始相对密度、摩擦因子)下对粉末连杆锻造致密过程的影响,运用塑性变形有限元软件DEFORM-3D对粉末连杆锻造过程进行了计算机模拟研究；研究结果表明,不同初始条件对粉末连杆锻造成形致密过程具有重要影响:(1)连杆锻造过程受到的等效应力集中在杆身部位,连杆两头的等效应力相对较小,说明其锻造过程各处所受等效应力不均匀,成形密度也不均匀；(2)初始相对密度较小的预锻坯锻造结束时,连杆大头处的材料不能达到致密,初始相对密度大的预成形坯,终锻致密效果好；(3)摩擦因数越大,连杆表面的材料流动阻力就越大,连杆大小两头就越难达到致密,说明摩擦因子对连杆相对密度分布均匀性有较大影响；通过对粉末连杆锻造致密过程影响的研究,为粉末连杆预锻坯和模具的优化设计及粉末锻造连杆的成形规律提供一定理论依据。

Simulation Study on Influence of Initial Conditions onDensification Process of Powder Forging

In order to study the effect of different initial conditions (initial relative density, friction factor) on the compacting process of powder connecting rod forging process, the plastic deformation finite element software DEFORM-3D was used to simulate the process of powder connecting rod forging. The results show that different initial conditions have an important effect on the compacting process of powder connecting rod forging. (1) The equivalent stress of connecting rod forging process is concentrated in the shaft part, and the equivalent stress of the two ends of the connecting rod is relatively small, which indicates that the equivalent stress is uneven and the forming density is not uniform in all parts of the forging process; 2) The initial relative density of small forging forging at the end of the big rod at the end of the material can not reach the dense, the initial relative density of the preform, the final forging densification effect; (3) the greater the friction factor, connecting rod The greater the resistance of the surface material flow, the greater the size of the connecting rod is more difficult to achieve compact, indicating that the friction factor on the relative density of the rod has a greater impact on uniformity. Through the research on the influence of the densification process of the powder connecting rod, the optimization design of pre forging billet and the die and the forming rule of the powder forging rod are provided.