hydrogen induced cracking in flux cored electrode welds
H ydrogen Induced Cracking (HIC), also called hydrogen assisted cracking (HAC) and cold cracking, is a common welding defect when welding heavy steel sections and steels with high carbon content. If you would like to learn more about the causes of HIC read Factors Influencing Hydrogen Induced Cracking. Diffusible Hydrogen Content in Rutile Flux-Cored Arc Welds Feb 07, 2013 · The objective of the current work was to establish the effect of flux-cored arc welding (FCAW) parameters, such as welding current, contact-tip to workpiece distance (CTWD) and shielding gas type, on diffusible hydrogen content for single run, horizontal position, bead-on-plate welds using seamed and seamless rutile consumable wires. The work included an investigation of arc
Hydrogen induced cracking can occur in the weld heat affected zone (HAZ) and in the fusion zone (FZ). While the reasons for cracking are the same, controlling the factors that cause cracking can be different for the HAZ and FZ. How to weld T-1 constructional alloy steelsbecause of the cracking. For example, many welds are subject to forces that tend to pull them apart. This means that a weld with hydrogen-induced cracks could fail under a lower force than expected depending on the extent of cracking. How to select the correct low hydrogen covered electrodes for shielded metal arc welding Low hydrogen covered Low Hydrogen Filler Metals - Welders, Welding Wire To avoid hydrogen induced cracking, the hydrogen level in the material must be held to a certain maximum level. This level is a function of the microstructure susceptibility, constraint (or restraint), and residual stresses. Microstructure susceptibility to hydrogen induced cracking often increases with increasing steel strength.
Jun 20, 2007 · This investigation examined the feasibility of using flux modification in the form of the addition of oxidizing ingredients to reduce the as-deposited hydrogen content of basic-type shielded metal arc welds. Additions of up to 16.3% micaceous iron oxide (MIO) to the flux formulation of an E7018-1 type electrode lowered the diffusible weld hydrogen content by approximately 70%. The Consequences and Control of Hydrogen in the Welding Oct 03, 2013 · Typically, hydrogen-induced cracking occurs at temperatures below 600 degrees Fahrenheit (more commonly around or below 300 degrees Fahrenheit) and within 48 hours of completing the weld. In some cases, it can occur as much a week after welding. WELDING CONSUMABLESThe filling remains dry throughout the entire process of storage and use in welded fabrication, preventing hydro-gen induced cracking caused by mois-
temperatures in high strength steel welds, so measures to reduce hydrogen induced cracking must rely on control of hydrogen level or microstructure or both. Measurements of weld hydrogen levels provide a way of assessing the degree to which a given electrode, flux or shielding gas may introduce hydrogen into the weld pool.