Effect of Cu Addition on Delayed Fracture Resistance of Low Carbon Steel for 1 470 MPa Grade Electric Resistance Welded Tube

Effects of Cu Addition on Hydrogen Absorption and Diffusion Properties of 1470 MPa Grade Thin-walled Steel in a Solution of HCl

“…This result dovetails with the fact that the exchange current density of Cu was smaller than that of Fe by one order of magnitude, which was reported by Uhlig and Revie. 32) Toyoda et al 24) proposed a mechanism for the effect of the addition of Cu on the delayed fracture resistance of 1 470 MPa grade steel immersed in a solution of HCl. Specifically, Toyoda et al suggested that the 1 or 2-mm metallic Cu particles precipitated on the steel surface suppressed the cathodic reaction and the introduction of hydrogen.…”

“…[20][21][22][23][24][25][26] Even under atmospheric conditions, the pH of the water film in the rust layer can decrease to 3 or less. 27) Toyoda et al 24) reported that the addition of Cu had a significant effect on the delayed fracture resistance of low-carbon martensitic 1 470 MPa grade steel immersed in a solution of HCl. And they also reported that the results of delayed fracture resistance in (a) an immersion test using 0.1 N-hydrochloric acid, (b) a cyclic corrosion test with 5% NaCl water spray, and (c) an atmospheric corrosion test had good correlation with each other.…”

Effects of Cu Addition on Hydrogen Absorption and Diffusion Properties of 1470 MPa Grade Thin-walled Steel Tube under Atmospheric Corrosion

“…[20][21][22][23][24][25][26] Furthermore, it was reported that even under atmospheric circumstances, the pH of condensed water in the rust layer could decrease to 3 or less. 27) Toyoda et al 24) reported substantial effects of Cu addition on the delayed fracture resistance of low carbon martensitic 1 470 MPa grade steel immersed in HCl solution. They also reported that the results of delayed fracture resistance in (a) © 2011 ISIJ an immersion test using 0.1N-hydrochloric acid, (b) a cyclic corrosion test with 5% NaCl water spray, and (c) an atmospheric corrosion test had good correlation with each other.…”

“…Table 1 shows the chemical composition and tensile strength of the 1 470 MPa grade steel tubes used for the atmospheric corrosion test, which are the same electric resistance welded tubes as previously reported. 24) CuLC represents Cu bearing steel which contains 0.15 mass% Cu. LC represents Cu free steel.…”

“…1, they have finely dispersed carbide in the martensite lath as a result of quenching and tempering before being formed into a tube under the condition that was previously reported. 24) The tube size was 31.8 mm in diameter, 2.0 mm in thickness and 150 mm long. An electro-deposition coat was not applied.…”