【作者】 王黎明；

【导师】 署恒木； 黄小光；

【作者基本信息】 中国石油大学(华东) ， 力学， 2016， 硕士

【摘要】 海洋工程结构由于其所处的服役环境,必然会同时遭受交变载荷和腐蚀环境的共同作用,腐蚀疲劳问题也成为了海洋结构钢使用寿命的主要影响因素。所以需要对其进行腐蚀疲劳特性的研究以及耐久性设计。本文以AH32钢作为腐蚀疲劳试验的研究对象,根据腐蚀试验、轴向拉伸试验、疲劳试验数据,分别得到其腐蚀性能、力学性能以及疲劳性能。在疲劳试验的基础上,对其试验机进行改装,设计了腐蚀环境箱和循环装置,满足腐蚀疲劳试验的条件。同时进行了预腐蚀疲劳和腐蚀疲劳试验,得到腐蚀疲劳的破坏效果优于预腐蚀疲劳,更甚于疲劳试验。并根据热力学原理、SEM形貌图对断口形成及破坏机理进行了定性分析。基于损伤力学理论,提出了两种腐蚀疲劳损伤模型。第一种是基于腐蚀损伤和预腐蚀疲劳损伤的累加模型,第二种是基于应力腐蚀损伤和疲劳损伤的非线性累加模型。通过设计试验,分别确定应力腐蚀的损伤参数、疲劳损伤参数,从而建立腐蚀疲劳损伤演化规律,用于腐蚀疲劳的寿命预测。结合海洋结构钢AH32腐蚀疲劳特性,以增强其抗腐蚀疲劳性能,提高寿命为目的,设计一套以表面处理,电弧喷涂金属涂层的延寿性工艺。并制备出镀锌和镀铬的两种试件,分别经过预腐蚀疲劳试验和腐蚀疲劳试验,根据镀锌、镀铬试件与裸钢试件寿命结果对比,发现两者的寿命都得到了一定程度的提升,在腐蚀疲劳试验中,两者寿命的提升比例分别能达到14.6%和22%,达到了延寿的效果。同时综合成本和效果,采用镀锌铬合金最为合理,可选用达克罗涂层,达到显著提高海洋结构钢的耐久性的目的。更多还原

【Abstract】 Ocean engineering structures due to its service environment,must be subjected to cyclic loading and corrosive environment at the same time,the corrosion fatigue problem has become the main factors influencing the service life of marine structural steel.So it is necessary to research corrosion fatigue characteristics and durability design.Taking AH32 steel as the research object of corrosion fatigue test,according to the corrosion test,axial tensile test and fatigue test data,respectively obtain its corrosion resistance,mechanical properties and fatigue performance.On the basis of fatigue test,the testing machine to be modified,designed the corrosion environment box and circulating device,prepared corrosion fatigue test conditions.The corrosion fatigue and pre-corrosion fatigue tests have been carried out at the same time,get the corrosion fatigue damage effect is superior to precorrosion fatigue,more than fatigue test.And according to the principle of thermodynamics,SEM topography of fracture formation and destruction mechanism has carried on the qualitative analysis.Based on the damage mechanics theory,two kinds of corrosion fatigue damage model is proposed.The first is based on the corrosion damage and pre-corrosion fatigue damage cumulative model,the second is based on the stress corrosion damage and fatigue damage nonlinear cumulative model.Through design experiment,respectively,to determine the stress corrosion damage parameter,the fatigue damage parameter,so as to establish corrosion fatigue damage evolution rule,used for corrosion fatigue life prediction.Combined with marine structural steel AH32 corrosion fatigue characteristics,in order to enhance its resistance to corrosion fatigue performance,improve life for the purpose,design a set of surface treatment,the technology of prolong life of arc spraying metal coating.And the two kinds of galvanized and chrome plating is prepared specimens,respectively after the corrosion fatigue test and pre-corrosion fatigue test,according to the results of galvanized,chrome plating specimen,compared with the bare steel specimen,its life got a certain level of ascension,in corrosion fatigue tests,the life of the ascending ratio can respectively reach 14.6% and 22%,to achieve the effect of the prolong life.Taking into account the cost and effect of Zinc and chrome,at the same time the most reasonable,can choose the dacromet coating,achieve the goal of significantly increase the durability of marine structural steel.更多还原