【Daily Question No. 348】December 20, 2018
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【Daily Question No. 348】December 20, 2018: Briefly explain what high-temperature hydrogen corrosion is. It is a chemical reaction that occurs under high temperature and pressure, where hydrogen that diffuses into steel reacts with unstable carbides to form methane bubbles; this leads to a decrease in the strength, ductility, and toughness of the steel, as well as intergranular fracture. (Unless otherwise specified, all questions and answers are based on hydrogenation units.) ) Correct: 3 wealth, Incorrect: 1 wealth ； Mass posting of posts – rated based on the lowest score ； Replies that are unrelated to the answer are considered spam and will be deleted immediately. For management purposes, if you need to view content from a few days ago, please go to https://bbs.hcbbs.com/home.php?mod=space&uid=3862647&do=thread&view=me&from=space through the summary post below
High-temperature hydrogen corrosion occurs under high temperature and pressure conditions, where hydrogen that diffuses into the steel reacts chemically with unstable carbides to form methane bubbles, leading to a decrease in the steel’s strength, ductility, and toughness as well as to intergranular fracture.
During the operation of a hydrogenation reactor, high temperature generally refers to temperatures above 240 degrees. The rate at which hydrogen enters the reactor increases as the temperature rises and also as the pressure increases. When the temperature and pressure are not maintained within the normal operating conditions, hydrogen enters the metal lattice too rapidly, causing it to react with carbon to produce methane; this leads to cracks or bulging on the metal surface, thereby reducing the strength and toughness of the reactor.
It is a chemical reaction that occurs under high temperature and pressure, where hydrogen diffusing into the steel reacts with unstable carbides to form methane bubbles, leading to a decrease in the steel’s strength, ductility, and toughness as well as degradation, accompanied by intergranular fracture.
Under high temperature and pressure conditions, hydrogen diffusing into the steel reacts chemically with unstable carbides to form methane bubbles, leading to a decrease in the steel’s strength, ductility, and toughness as well as degradation, accompanied by intergranular fracture.
Under high temperature and pressure, hydrogen reacts with carbon in steel to cause hydrogen embrittlement
Hydrogen infiltrates steel under high temperature and pressure, and then forms methane with unstable carbides. Methane in steel does not easily escape, causing cracks and bubbling in the steel, as well as a significant reduction in its strength and toughness.
High-temperature hydrogen corrosion is primarily a chemical corrosion that occurs at high temperatures when the hydrogen partial pressure reaches a certain level, caused by the formation of methane bubbles inside
Corrosion, or hydrogen attack, occurs when steel is exposed to a high-temperature, high-pressure hydrogen environment; hydrogen atoms react with unstable carbides on the surface of the equipment or penetrate into the steel, resulting in the formation of methane and causing decarburization of the steel, which leads to permanent damage to its mechanical strength. The methane generated inside the steel cannot escape and accumulates there, creating high local pressures that lead to severe bulging and cracking.
It refers to the situation where steel is exposed to a high-temperature hydrogen environment; hydrogen atoms react with unstable carbides on the surface of the equipment or penetrate into the steel, producing methane and causing decarburization of the steel, which results in permanent damage to its mechanical strength. The methane generated inside the steel cannot escape and accumulates there, creating high local pressures that lead to severe bulging and cracking.