What kind of coefficient is the J coefficient in a hydrogenation reactor?
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This post was last edited by Desert Fish on 2019-2-16 at 13:06
→What are the J coefficient and X coefficient for alloy steels? The ΔJ coefficient is primarily used to control the impurity elements in the steel; its calculation formula is: J = (P + Sn) * (Si + Mn) * 10,000. The ΔX coefficient is mainly used to control the impurity elements in the weld; its calculation formula is: X = (10P + 5Sb + 4Sb + As) * 100
Why control the J and X coefficients? The essence of controlling the J coefficient and the X coefficient is to control the content of impurity elements in the metal. Why is it necessary to control these chemical elements? Since these elements are the main culprits behind temper embrittlement, it is they that cause an increase in the Fracture Appearance Transition Temperature at tempering temperatures, resulting in a decrease in the metal’s impact toughness. Studies have shown that at the tempering temperature, trace elements such as P, Sn, Sb, and As accumulate at the grain boundaries, with element P having the greatest impact; it weakens the intergranular bonding force. Mn and Si can promote the segregation of P, thereby exacerbating embrittlement.