药芯焊丝熔滴过渡形态与焊缝扩散氢关系研究进展OA

The research progress on the relationship between droplet transfer mode of gas shielded flux cored wire and diffusion hydrogen in the weld metal was reviewed.The results show that the reasonable matching of welding current and arc voltage is the decisive factor to obtain satisfactory usability.TiO2,Al2O3,SiO2,Si-Fe and other core compositions make the dominant surface tension Fσ and gas repulsive force Fq on the droplet decrease,the droplets become finer,and the diffusion hydrogen content in the weld increases.With the increase of powder filling ratio KC,the downward electromagnetic force Fem on the droplets increases,and the droplets are refined,which leads to the increase of diffusion hydrogen content in the weld.All the changes in process parameters that make droplet refinement can lead to the increase of diffusion hydrogen in the weld.The theoretical basis for this is that fine droplets have a larger specific surface area,and more hydrogen is carried in the arc,and more hydrogen enters the molten pool.