Abstract The purpose of this study is to understand the effect of laser welding parameters on the formation of hourglass shaped welds in low carbon steel. Transient laser welding is modeled in ANSYS to simulate the coupled heat-transfer/fluid-flow behavior that produces corresponding hourglass shaped melt pool geometry. Characteristics of the hourglass mode are full narrow penetration and wide surface of molten pool. Recoil pressure induced by rapid metal vaporization strikes the melt pool to form a deep and narrow key hole. Simultaneously, surface tension minimizing its surface free energy primarily acts to widen the melt pool. Comparison of the weld geometries show that welding parameters associated with changes in the melt fluid dynamics are of great importance in the formation of the hourglass shaped melt pool during laser welding.

中文翻译：

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激光焊接中沙漏焊缝形成的数值模拟

摘要 本研究的目的是了解激光焊接参数对低碳钢沙漏形焊缝形成的影响。瞬态激光焊接在 ANSYS 中建模，以模拟产生相应沙漏形熔池几何形状的传​​热/流体流动耦合行为。沙漏模式的特点是全窄渗透和宽熔池表面。金属快速汽化引起的反冲压力撞击熔池，形成一个又深又窄的关键孔。同时，最小化其表面自由能的表面张力主要用于加宽熔池。焊缝几何形状的比较表明，与熔体流体动力学变化相关的焊接参数对于激光焊接过程中沙漏形熔池的形成非常重要。