Test method for representing influence of hydrogen on crack initiation performance of high-steel-grade pipeline steel

Abstract

The invention discloses a test method for representing influence of hydrogen on crack initiation performance of high-grade pipeline steel. The method comprises steps that electrochemical hydrogen charging of a plurality of first samples and second samples which are made of a high-steel-grade pipeline steel weld joint material is conducted; after hydrogen filling is finished, impact tests at different temperatures are conducted on the multiple first samples obtained after hydrogen filling, the impact work of the multiple first samples obtained after hydrogen filling is obtained, and the impactwork of the multiple first samples obtained after hydrogen filling is compared with the crack initiation work of a high-steel-grade pipeline steel weld joint; a crack propagation resistance test on the second samples after hydrogen filling is conducted, a crack propagation resistance curve of the second samples is obtained after hydrogen filling, the crack tip opening displacement is obtained, whether a value of the crack tip opening displacement is larger than 0.1 mm or not is judged, the crack initiation resistance of the high-steel-grade pipeline steel weld joint material is determined, anda basis is provided for judging the crack initiation performance of the high-steel-grade pipeline steel after the high-steel-grade pipeline steel bears the hydrogen environment of a certain degree.

Description

technical field [0001] The invention relates to the field of research on hydrogen-induced plasticity loss of high-grade pipeline steel, in particular to a test method for characterizing the effect of hydrogen on the crack initiation performance of high-grade pipeline steel. Background technique [0002] With the increasing demand for oil and natural gas, the delivery pressure and pipe diameter of pipelines are also increasing. In order to meet the requirements of oil and gas long-distance transmission pressure and pipeline diameter, high-grade pipeline steel is mostly used at present. However, if hydrogen exists in the weld material of high-grade pipeline steel, the risk of crack brittle initiation will be aggravated, which will seriously affect the safety of oil and gas transportation. Therefore, it is necessary to explore the effect of hydrogen on the crack initiation properties of high-grade pipeline steel. [0003] At present, in the prior art, the in-situ slow tensile...

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Problems solved by technology

[0003] At present, in the prior art, the in-situ slow tensile test is usually used as a method to evaluate the hydrogen embrittlement susceptibility of high-grade pipeline steel. Hydrogen embrittlement susceptibility of high-grade pipeline steel, however, there is no test and research method for the crack initiation performance of high-grade pipeline steel after being subjected to a certain degree of hydrogen environment in the prior art

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