Container and Storage Devices Section: [Daily Question] 2011.04.24
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What are the main factors of stress corrosion in short-answer questions? Which media can cause stress corrosion in carbon steel and low-alloy steel? Answer: Tensile stress and corrosive media (environment) are present. NaOH, wet H2S, liquid ammonia, high-temperature and high-pressure hydrogen corrosion environments. 1: Those who participate and answer correctly will be rewarded; the maximum number of extra points is 50. Replies ； 2: Please hide your replies. The method for doing this is: http://bbs.hcbbs.com/thread-492556-1-1.html. Those who do not hide their replies or edit them after posting will not be awarded a reward ； 3: Please actively provide one question per day at http://bbs.hcbbs.com/thread-781748-1-1.html
This post was last edited by Zhang Junmeng on 2011-4-24 at 12:31: tensile stress, and corrosive media (environment) are present. NaOH, wet hydrogen sulfide, liquid ammonia, high-temperature and high-pressure hydrogen corrosion environments
Answer: Tensile stress and corrosive media (environment) are present. NaOH, wet H2S, liquid ammonia, high-temperature and high-pressure hydrogen corrosion environments
Stress corrosion cracking (SCC): A brittle fracture of metal materials caused by the combined effect of tensile stress and a specific environment. For CS, AS: alkali embrittlement, nitrate embrittlement, ammonia embrittlement (liquid ammonia), hydrogen embrittlement, sulfides, industrial cooling water, carbonates, etc.
Reply to 1# Deep Blue Expectation: 1. Reasons: tensile stress, corrosive agents. 2. NaOH, H2S, hydrogen environment
Tensile stress and a corrosive medium (environment) are present. NaOH, wet H2S, liquid ammonia, high-temperature and high-pressure hydrogen corrosion environments
The main factors of stress corrosion are tensile stress and the presence of a corrosive medium (environment). NaOH, wet H2S, liquid ammonia, and high-temperature and high-pressure hydrogen corrosion environments can cause stress corrosion in carbon steel and low-alloy steel.
Reply 1# Deep Blue Yipan: Tensile stress and corrosive media (environment) are present. NaOH, wet H2S, liquid ammonia, high-temperature and high-pressure hydrogen corrosion environments
This post was last edited by Shenlan Yipan on 2011-4-24 at 17:53. Stress corrosion is a complex phenomenon: when no stress is present, the growth of corrosion cracks is very slow, so that cracking does not occur during the material’s service life. When stress is present and reaches a certain level, the metal can crack even though corrosion is not severe. Such cracks are brittle and occur without any obvious signs, making them likely to lead to catastrophic accidents. For brass, the corrosive media include ammonia gas and solutions, ferric chloride, and wet sulfur dioxide; for titanium, the media include methanol or ethanol containing hydrochloric acid, as well as molten sodium chloride
Reply to 1# Deep Blue Hope: Stress corrosion cracking is a type of failure that occurs in metals under the combined effect of stress (tensile stress) and a corrosive environment (along with certain temperature conditions). Stress corrosion is a complex phenomenon – when no stress is present, the growth of corrosion cracks is very slow, so no cracking occurs during the material’s service life. However, when stress reaches a certain level, the metal can crack even in an environment where corrosion is not severe. Since such cracking is brittle and occurs without any obvious signs, it can lead to catastrophic failures. For carbon steel and low-alloy steel, the corrosive environments can include alkaline solutions, nitrate solutions, anhydrous ammonia, wet hydrogen sulfide, acetic acid, etc
1. Tensile stress: A combination of specific materials and media, generally leading to delayed brittle fracture. 2. Alkaline solutions, wet hydrogen sulfide, ammonia solutions, nitrate solutions, etc