【作者】 傅育文；

【导师】 胡绳荪；

【作者基本信息】 天津大学 ， 材料加工工程， 2004， 硕士

【摘要】 小孔等离子弧焊接是一种高能高效焊接方法，具有十分广阔的应用前景。但是由于等离子弧焊接工艺参数匹配区间窄，使得等离子弧焊接中小孔的稳定性差，因而等离子弧焊接过程及焊接质量稳定性差。如何提高等离子弧焊接质量的稳定性是当前该领域研究的前沿课题之一。脉冲等离子弧焊接中通过脉冲参数的调整可以调节工件的热输入量，拓宽等离子弧焊接参数匹配区间，从而可以提高等离子弧焊接质量的稳定性，为此本文对脉冲等离子弧焊接系统及控制进行了研究。本文研制了一套以Atmega128单片机为核心的脉冲等离子弧焊接自动控制系统。该系统不仅可以进行脉冲等离子弧焊接，而且可以实现脉冲等离子弧焊接的熔透控制。在脉冲等离子弧焊接时，脉冲电流参数可以通过单片机控制系统进行设定，为深入研究脉冲焊电流参数对等离子弧脉冲焊接质量的影响提供了一个研究平台。在脉冲等离子弧熔透控制中，进行了脉冲等离子弧焊接实验研究，初步分析了脉冲参数对焊接质量的影响规律，提出了两种熔透控制策略：即脉冲峰值时间控制和脉冲峰值电流大小控制。并进行了脉冲等离子弧熔透控制模拟实验，实验结果表明，本文所提出的熔透控制策略是可行的。更多还原

【Abstract】 Keyhole plasma arc welding (PAW) is a high-octane and high-efficiency technology, it has a good foreground. However, the welding parameter matching zone of PAW is very narrow. It makes the keyhole unstable, so that the welding quality is unstable. Therefore, how to improve the welding stability in the research field of plasma arc welding is a promising item. Through adjusting the pulse welding parameter, the system can adjust heat input of welding and can increase the welding parameter matching zone of PAW. So it can improve the stability of welding. Therefore, pulse plasma arc welding and the control system of PAW are studied in the paper. A single-chip control system based on the chip Atmega128 is designed in the paper. The system can not only be used in pulse plasma arc welding, but also can be used in penetration controlling in plasma arc welding. In pulse plasma arc welding, we can input pulse welding parameter through the keyboard of the single-chip system. It provides a platform to study deeply the effect of pulse parameter to welding quality. In penetration control system of PAW, welding experiments were carried out and two tactics is designed: pulse time control and pulse current control. The experiments showed that the single-chip control system can do well according to the program designed and the tactics are viable.更多还原