X65管线钢原位氢阴极充电后氢脆敏感性及断裂韧性下降的研究

Investigation of Hydrogen Embrittlement Susceptibility and Fracture Toughness Drop after in situ Hydrogen Cathodic Charging for an X65 Pipeline Steel.

作者信息

Kyriakopoulou Helen P, Karmiris-Obratański Panagiotis, Tazedakis Athanasios S, Daniolos Nikoalos M, Dourdounis Efthymios C, Manolakos Dimitrios E, Pantelis Dimitrios

机构信息

National Technical University of Athens, Shipbuilding Technology Laboratory, School of Naval Architecture and Marine Engineering, Athens 15780, Greece.

AGH University of Science and Technology, School of Mechanical Engineering and Robotics, Mickiewicza 30, 30-059 Cracow, Poland.

出版信息

Micromachines (Basel). 2020 Apr 20;11(4):430. doi: 10.3390/mi11040430.

DOI:10.3390/mi11040430

PMID:32325971

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7231333/

Abstract

The present research focuses on the investigation of an in situ hydrogen charging effect during Crack Tip Opening Displacement testing (CTOD) on the fracture toughness properties of X65 pipeline steel. This grade of steel belongs to the broader category of High Strength Low Alloy Steels (HSLA), and its microstructure consists of equiaxed ferritic and bainitic grains with a low volume fraction of degenerated pearlite islands. The studied X65 steel specimens were extracted from pipes with 19.15 mm wall thickness. The fracture toughness parameters were determined after imposing the fatigue pre-cracked specimens on air, on a specific electrolytic cell under a slow strain rate bending loading (according to ASTM G147-98, BS7448, and ISO12135 standards). Concerning the results of this study, in the first phase the hydrogen cations' penetration depth, the diffusion coefficient of molecular and atomic hydrogen, and the surficial density of blisters were determined. Next, the characteristic parameters related to fracture toughness (such as J, KQ, CTOD, CTOD) were calculated by the aid of the Force-Crack Mouth Open Displacement curves and the relevant analytical equations.

摘要

本研究聚焦于在X65管线钢断裂韧性性能的裂纹尖端张开位移测试（CTOD）过程中对原位充氢效应的研究。这种钢种属于高强度低合金钢（HSLA）这一宽泛类别，其微观结构由等轴铁素体和贝氏体晶粒组成，退化珠光体岛的体积分数较低。所研究的X65钢试样取自壁厚为19.15毫米的管道。在对疲劳预裂纹试样在空气中、在特定电解槽中进行慢应变速率弯曲加载后（根据ASTM G147 - 98、BS7448和ISO12135标准）测定断裂韧性参数。关于本研究的结果，在第一阶段测定了氢阳离子的渗透深度、分子氢和原子氢的扩散系数以及水泡的表面密度。接下来，借助力 - 裂纹开口位移曲线和相关解析方程计算了与断裂韧性相关的特征参数（如J、KQ、CTOD、CTOD）。