焊接工艺参数对FGH96合金惯性摩擦焊过程材料塑性流动行为的影响

采用数值模拟方法对FGH96合金惯性摩擦焊过程进行分析,获得温度、轴向缩短量、材料流动与飞边四者之间的关系,着重研究初始转速与轴向压力等焊接工艺参数对材料塑性流动行为的影响规律。研究结果表明:在惯性摩擦焊初始阶段,材料温度与流动速度较低,无飞边产生;随着焊接过程的进行,材料的温度与流动速度呈现先升高后降低的规律;在焊接过程进入稳态后,摩擦面中心区域的材料主要沿试件的旋转方向流动,而摩擦面上两边界附近的材料向面外流动并形成飞边,飞边尺寸与弯曲程度随焊接时间的增加而增加。同时,随到摩擦面距离的增加,材料的流动速度逐渐降低且材料沿轴向流动的速度分量增大。结合FGH96合金惯性摩擦焊轴向缩短量的数值模拟结果,解释了从提高材料流动速度的幅度上看增加轴向压力优于初始转速的原因。

Effect of Welding Process Parameters on Material Flow Behavior of FGH96 Alloy in Inertia Friction Welding

The inertia friction welding process of FGH96 alloy is investigated by conducting numerical simulation.The temperature,axial shortening,material flow and flash of weldment are obtained and the effects of welding process parameters on the material flow behavior are analyzed,such as initial rotational speed and axial pressure.The results show that the temperature and the flow velocity of material at friction surface are both low in the welding initial process and the flash doesn’t appear.With the increase of welding time,the temperature and the flow velocity of material increases and then decreases.When the welding process reaches the stable state,the material near the two edges of friction surface flows towards the outside of friction surface while the direction of material flow near the middle of friction surface is mainly the same as the rotational direction of weldment.Moreover,with the increase of distance away from the friction surface,the flow velocity of material gradually decreases while the component of velocity along the axial direction increases.From the viewpoint of increasing the material flow velocity,the increase of upset press is better than that of initial rotational speed,which can be explained by the axial shortening of weldment of FGH96 alloy in the inertia friction welding.