X80管线钢电化学充氢行为的-研究 冶金工程毕业设计.doc

摘 要 石油、天然气输送管线在服役过程中,环境中的氢不可避免的进入到管线材料内部,产生氢损伤。管线钢中的氢可能导致氢脆和氢致开裂，裂纹扩展可能与进入钢中的氢含量有关。 本论文以X80管线钢为样品，在0.5mol/L的H2SO4溶液中用电化学充氢的方法进行研究，探讨试样在不同条件下的吸收氢的规律，为后面的耦合实验提供充氢依据。本实验共分两组：第一组固定充氢电流密度，改变充氢时间，研究在相同充氢电流密度下，充氢时间对氢吸收的影响。第二组固定充氢时间，改变充氢电流密度，研究在相同充氢时间下，充氢电流密度对氢吸收的影响。钢中氢的含量主要采用排油集气法测定,以获得钢中的氢含量。 实验获得如下结果：固定充氢电流密度不变，随着充氢时间的延长，材料中的可扩散氢含量CH 逐渐增加.充氢时间达到5h时，材料中的可扩散氢含量CH 基本饱和，再延长充氢时间，氢含量的增幅很小。固定充氢时间不变，随着充氢电流密度的增大，材料中的可扩散氢含量CH 逐渐增加，充氢电流密度达到18mA/cm2时，材料中的可扩散氢含量CH 基本饱和，再增大充氢电流密度，氢含量的增幅很小。 关键词：管线钢；电流密度；氢脆；耦合 ABSTRACT In oil, natural gas transportation pipeline service process, the hydrogen in environment inevitably enters the interior piping materials, generating hydrogen damage. Pipeline steel of hydrogen could lead to hydrogen induced cracking and hydrogen, it has to do with hydrogen content in steel. The paper used X80 pipeline steel as samples, in 0.5 mol/L - H2SO4 solution using electrochemical hydrogen charging, to explore specimen under different conditions of hydrogen absorption and provide a basis for hydrogen in behind of coupling experiment. This experiment is divided into two groups: the first group is in changing hydrogen filling time, fixed current density of hydrogen to study under the same current density of hydrogen, hydrogen filling time for hydrogen absorption. A second group is in changing the current density of hydrogen, fixed hydrogen charging time, to study the hydrogen filled in the same time, the current density of hydrogen effects on hydrogen absorption. Hydrogen content in steel mainly adopts discharge of oil gas collection method, in order to obtain hydrogen content in steel. Experiments obtain the following results: fixed hydrogen charging current density is constant, as the extension of hydrogen filling time, material can be diffusion hydrogen content of CH increased gradually. In hydrogen filling time at 5h, the material can be diffusion hydrogen content of CH basic saturated, and in extend the time of hydroge