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激光深熔焊接过程的稳定性与焊接时的金属蒸气动力学行为密切相关。采取特殊试验方法对高功率激光深熔焊接小孔内喷出的金属蒸气流力学特性进行研究,观察分析了在金属蒸气流的推动作用下自由下落金属球的速度变化以及从小孔飞出的飞溅熔滴速度大小。结果得出,激光深熔焊接过程中激光功率越大、离小孔开口处距离越小,由小孔喷出的金属蒸气流的推力越大;相同激光功率焊接时,飞出小孔的飞溅具有的速度和动能远大于金属蒸气推动金属球获得的速度和动能增量,揭示了飞溅在飞出小孔前已经获得较大动能。由此得出,相比于小孔内高压蒸气流和流动的焊接熔池熔液的动力学作用,从小孔喷出后的金属蒸气流的推动作用甚微。
The stability of the laser deep-penetration welding process is closely related to the dynamic behavior of the metal vapor during welding. A special test method was used to study the mechanical properties of the metal vapor emitted from the deep hole of the high-power laser penetration welding. The variation of the velocity of the free-falling metal ball under the action of the metal vapor flow was observed. Splash droplet size. The results show that the greater the laser power during laser deep-penetration welding, the smaller the distance from the opening of the hole, the larger the thrust of the metal vapor stream ejected from the hole; the splash of the hole when the same laser power is welded Has a much greater velocity and kinetic energy than the incremental velocity and kinetic energy gained by the metal vapor driving the metal ball, revealing that the splash has gained a great deal of momentum before it flies out of the orifice. It follows that, compared to the kinetic effects of the high pressure vapor stream in the orifice and the flowing molten weld pool melt, the flow of the metal vapor stream ejected from the orifice is negligible.