Hydrogen-assisted cracking of T-250 maraging steel

• DOI: 10.1016/j.msea.2007.02.111
• Publication Date: 2007-03-04T11:52:47Z
• Authors: Y.P. Zhang; D.M. Shi; W.Y. Chu; L.J. Qiao; Y.L. Shi; S.L. Zheng; S.B. Wang
• Keywords: Maraging steel; Intensity

Abstract Hydrogen-assisted cracking (HAC) of T-250 maraging steel has been studied. The results showed that HAC could occur in air when the relative humidity (RH) was ≥30%. The arrested threshold stress intensity factor, KIH (MPa m1/2), decreases linearly with increasing the logarithm of hydrogen concentration entered into the samples during putting in humid air or charging in the solution, C (ppm), i.e. KIH = 49.5–26.1 ln C. The threshold stress intensity factor for the crack initiating from notch tip in humid air with RH = 82%, KIH(ρ), increases with increasing the square root of notch radius ρ, as ρ > ρ0 = 0.08 mm, i.e. K IH ( ρ > 0.08 mm ) = − 32.7 + 244.9 ρ , however, when ρ ≤ ρ0, KIH(ρ ≤ 0.08 mm) = KIH = 37.5 MPa m1/2.