In order to study the application of gas fire extinguishing agents in civil aircraft fire extinguishing systems,the corrosion characteristics and mechanisms of Halon 1301 and CF_(3)I on AZ80A magnesium alloy were comp...In order to study the application of gas fire extinguishing agents in civil aircraft fire extinguishing systems,the corrosion characteristics and mechanisms of Halon 1301 and CF_(3)I on AZ80A magnesium alloy were comparatively analyzed.The experimental methods combined with density functional theory were applied to explore the corrosion mechanism.The results indicate that Halon 1301 and CF_(3)I exhibit good compatibility with AZ80A magnesium alloy through physical adsorption at room temperature and pressure,where Halon 1301 has a more stable adsorption configuration.However,with increasing temperature,pyrolysis reactions occur leading to the formation of fluorine containing corrosive substances which can react with magnesium alloy to generate the corrosion production of MgF_(2) and coke.Although MgF_(2) and coke can partically reduce reaction rates and protect against corrosion,the presence of MgF_(2) promotes further pyrolysis,generating more corrosion products.Consequently,the accumulation of corrosion products leads to a loss of metallic luster and a decline in mechanical properties of magnesium alloy along with interfacial cracking due to mutual extrusion between MgF_(2) and carbon deposition layers.These studies offer theoretical guidance for utilizing CF_(3)I in civil aircraft fire extinguishing systems while facilitating rapid screening for efficient clean gas extinguishing agents.展开更多
基金supported by the Joint Funds of the National Natural Science Foundation of China“False alarm immunity fire detection mechanism and key technologies of civil aviation aircraft cargo compartment”[Grant No.U213320003]Science and Technology Program of Tianjin“Research on fire characteristics and advanced halo-carbon fire extinguishing technology of domestic civil aircraft”[Grant No.21JCZDJC00810].
文摘In order to study the application of gas fire extinguishing agents in civil aircraft fire extinguishing systems,the corrosion characteristics and mechanisms of Halon 1301 and CF_(3)I on AZ80A magnesium alloy were comparatively analyzed.The experimental methods combined with density functional theory were applied to explore the corrosion mechanism.The results indicate that Halon 1301 and CF_(3)I exhibit good compatibility with AZ80A magnesium alloy through physical adsorption at room temperature and pressure,where Halon 1301 has a more stable adsorption configuration.However,with increasing temperature,pyrolysis reactions occur leading to the formation of fluorine containing corrosive substances which can react with magnesium alloy to generate the corrosion production of MgF_(2) and coke.Although MgF_(2) and coke can partically reduce reaction rates and protect against corrosion,the presence of MgF_(2) promotes further pyrolysis,generating more corrosion products.Consequently,the accumulation of corrosion products leads to a loss of metallic luster and a decline in mechanical properties of magnesium alloy along with interfacial cracking due to mutual extrusion between MgF_(2) and carbon deposition layers.These studies offer theoretical guidance for utilizing CF_(3)I in civil aircraft fire extinguishing systems while facilitating rapid screening for efficient clean gas extinguishing agents.
