The Study On Metal Transfer And Operation Performance Of Rutile Gas Shielded Flux-cored Wire

The worldwide research development of metal transfer and operation performance of rutile flux-cored arc welding (FCAW) is reviewed. The study director and main content of this paper are proposed.The metal transfer, operation performance, effect factor, metallurgy characteristic of three rutile flux-cored wires are investigated by collecting droplet in water, high speed cinema photographic technique, Analysator Hannover, hardfacing on the plate and physical-chemical analysis. The wires used in experiment are YC-YJ502(Q) (marked A), Supercored 71H (marked B), DW-100 (marked C). The result shows: the welding current is thekey solution to the metal transfer. The droplet becomes smaller, and the transfer frequency goes up as the increasing current. The current is also critical to the operation performance, and there is a current limit in which the usability is the best. In the welding condition of 240A, 28V, the metal transfer mode is non-axis drop spray transfer. The large angle and small angle repelled transfer mode, and the important effect on usability are discovered. A wire is in large angle repelled transfer mode, the operation performance is poor, B wire metal transfer in small angle repelled transfer, the operation performance is the best, the above two mode appear alternately in the C wire, so the operation performance is intermediate. The droplet of B wire is the smallest while the transfer frequency is the highest among the three wires, A wire is inferior to B wire, the case of C wire is converse to B wire. The difference of composition of Mn, Si in the droplet reaction shows that because Si added to the droplet of B wire is more than A wire and C wire, the droplet of B wire is smaller than A wire and C wire, and the droplet of C wire is the biggest among them.The phenomena of droplet transferring deviated form the wire axis in different angle and the effect on the operation performance are discovered first time in this paper. The "large angle repelledtransfer, transfer interval time" are put forth to revalue the metal transfer and the usability which enrich the metal transfer theory to some degree.This paper exposed the relationship between the metal transfer and the usability of the three typical rutile flux-cored wires. This work give the guidance to select correct operating conditions of welding, so it has the practice value.This paper also shows up the relationship between the welding metallurgy and metal transfer and the usability by analysis of the composition of sheath, droplet and deposited metal.