基于脉冲微束等离子弧焊的快速成形系统中实时自适应送丝方式

REAL-TIME ADAPTIVE WIRE FEEDING IN PULSED MICRO-PLASMA ARC WELDING BASED ON RAPID PROTOTYPING SYSTEM

对基于脉冲微束等离子弧焊的直接金属快速成形系统中,填充金属丝的熔滴过渡方式和送丝方向对成形轨迹质量的影响进行了研究。研究结果表明:“搭桥过渡”方式形成的轨迹形态连续、光滑;送丝方向固定的方式在成形与送丝方向间夹角过大的轨迹时,会发生熔滴未完全熔于熔池、金属丝与已凝固成形轨迹发生干涉等缺陷。根据研究结果研制了一个基于成形件断面轮廓实时调整送丝方向的自适应送丝子系统。论述了转角、合成速度、加速度等控制参数的确定算法。对自适应送丝方式和方向固定的送丝方式进行了对比试验。结果显示:自适应送丝方式避免了熔滴未完全熔于熔池、金属丝与已凝固成形轨迹发生干涉等缺陷,对保证成形轨迹的质量有显著作用。

The impact of the droplet transfer process and the wire feeding direction on the deposited track＇s quality of the direct metal rapid prototyping using pulsed micro-plasma arc welding （PMPAW） is researched. The results show that the smoother deposited track can be deposited with the bridgingtransfer. Constant wire feeding direction during the deposition process brings off some defects, for example, partial droplet does not melt into molten pool and filler wire is interfered with the solidified deposited track when some tracks have larger angle with wire feeding direction. An adaptive wire feeding subsystem that can adjust the wire feeding direction based on the part＇s section contour in a real-time mode is developed to avoid the defect and the interference. The algorithm of angle, resultant velocity and acceleration is expatiated. Some experiments are carried out to compare the deposited track＇s qualities of different wire feeding modes. The results show that the adaptive wire feeding system can avoid the deposition defects and interference and ensure the deposited track＇s quality obviously.