Study on hydrogen assisted cracking susceptibility of HSLA steel by implant test
Autor: | Shaju K. Albert, Gopa Chakraborty, R. Rejeesh |
---|---|
Jazyk: | angličtina |
Rok vydání: | 2016 |
Předmět: |
0209 industrial biotechnology
Heat-affected zone Materials science Computational Mechanics Shielded metal arc welding 02 engineering and technology Welding Electric resistance welding law.invention Gas metal arc welding 020901 industrial engineering & automation law Lower critical stress Composite material Mechanical Engineering Gas tungsten arc welding Metallurgy Shielding gas Metals and Alloys Hydrogen assisted cracking 021001 nanoscience & nanotechnology Implant test Military Science HSLA steel Ceramics and Composites Diffusible hydrogen Arc welding 0210 nano-technology |
Zdroj: | Defence Technology, Vol 12, Iss 6, Pp 490-495 (2016) |
ISSN: | 2214-9147 |
Popis: | DMR-249A is an indigenously developed high strength low alloy steel for Indian ship building industry for making ship-hull and is extensively used in the construction of war ships and submarines. Welding electrodes conforming to SFA 5.5 AWS E8018 C1 has been indigenously developed for welding of this steel using shielded metal arc welding process. In the present study, susceptibility to hydrogen assisted cracking of DMR-249A steel welds made using this electrode has been assessed using implant test. Implant tests were conducted using this electrode at two different levels of diffusible hydrogen, measured using gas chromatography technique. It is observed that both the steel and the welding consumable are not susceptible to hydrogen assisted cracking even with a high diffusible hydrogen level of 9 mL/100g of weld metal. In implant tests, specimen did not fracture even after loading to stress levels higher than the yield strength of the base metal. The good resistance of this steel and the welding consumable, even with high levels of diffusible hydrogen, is attributed to absence of a susceptible microstructure in both the weld metal and heat affected zone. Hence, this study shows that, in the absence of a susceptible microstructure, hydrogen assisted cracking is unlikely to occur even if hydrogen level is high. It also confirms that in welding of DMR-249A with indigenously developed E8018 C1 electrode, hydrogen assisted cracking is not a concern and no preheating is required to avoid it during welding. |
Databáze: | OpenAIRE |
Externí odkaz: |