热处理温度对船用5083-H116铝合金焊件力学性能及抗腐蚀性影响研究

Effects of Heat Treatment Temperature on Mechanical Properties and Corrosion Resistance of Marine 5083-H116 Aluminum Alloy Weldment

通过硬度、拉伸试验、硝酸腐蚀质量损失测试及微观组织观察,研究了不同退火温度对5083-H116镁铝合金的焊缝区、热影响区和母材的力学性能和抗蚀性能影响。研究结果表明:焊缝熔融凝固后组织主要为柱状晶及等轴晶组织结构,其抗拉强度已降至最低,并不受焊后退火温度影响。热影响区因高温热影响主要呈现出晶界成长及再结晶组织,而母材区主要为部分再结晶与回复结构。另外,β相较易沿热影响区与母材区的晶界析出,严重影响其力学强度与抗腐蚀性能,其中再结晶组织的抗拉强度较低,且敏化后腐蚀程度较回复组织严重。研究成果可供造船厂铝合金舰艇建造及维修提供理论依据。

The effects of different annealing temperature on the mechanical properties and corrosion resistance of weldzone, heat affected zone and base material of 5083-H116 aluminum magnesium alloy were studied by means of hardness test,tensile test, nitric acid corrosion weight loss test and microstructure observation. The results show that the weld microstructureis mainly eolunmar and equiaxed grains after solidification, and its tensile strength is minimum, which is not affected byannealing temperature after welding. Due to high temperature thermal effect, the heat affected zone presents grain boundarygrowth and recrystallization, and base metal is partial recrystallization and recovery structure. In addition, the 13 phase is easierto precipitate along the grain boundaries of heat affected zone and base metal, which seriously affects its mechanical strengthand corrosion resistance. The tensile strength of recrystallization microstructure is lower, and the degree of corrosion aftersensitization is more serious. The research results can provide theoretical basis for the construction and maintenance ofaluminum alloy naval vessels in the shipyard.