Open AccessPhysical Nature of the Processes in Structure Forming, Phase and Chemical Composition of pipe Permanent Joints when MMA Welding
Author(s) -
Dmitriy P. Il’yaschenko,
Dmitry А. Chinakhov,
В. И. Данилов,
I D Sadykov
Publication year - 2016
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/125/1/012010
Subject(s) - welding , materials science , heat affected zone , joint (building) , metallurgy , chemical composition , microstructure , phase (matter) , electrode , composite material , electric resistance welding , flash welding , gas metal arc welding , structural engineering , chemistry , engineering , organic chemistry
The paper outlines peculiarities of structure formation, phase and chemical composition in regard to heat content in molten electrode metal beads when pipe steel (steel 09G2S) welding using power sources with various energy characteristics. Mathematical calculations indicate an inverter power source provides minor heat content into the bead of electrode metal when welding. Experimental research has pointed at 4-9 % increase in impact strength of joints produced using an inverter power source in comparison with samples produced applying a diode rectifier. The following factors can possibly give rise to the increasing impact strength: difference in microstructures of weld joints, up to 50% shortening ferritic plates in metal of weld joint, change in dimensions of ferritic grains in the heat-affected zone by as much as 17.5 %, and decrease in the extent of heat-affected zone by 50%