热输入对高强钢GMAW增材组织及力学性能影响

在不同热输入(10.66 k J/cm、13.34 k J/cm、15.70 k J/cm)下对ER130S-G低合金高强钢进行GMAW增材试验,研究热输入对增材结构显微组织、室温拉伸性能的影响。结果表明:增材结构组织可分为受热区和未受热区,受热区组织主要由针状铁素体和粒状贝氏体组成,未受热区主要为粗大的柱状晶。随着热输入的增加,粒状贝氏体含量减少,针状铁素体增加,同时出现部分板条马氏体。室温下抗拉强度和断后伸长率均呈先增大后减小的趋势,在热输入为13.34 k J/cm时,力学性能最佳,拉伸断口均为韧性断口。

Effect of Heat Input on Microstructure and Mechanical Properties of High Strength Steel GMAW Additives

The effect of heat input on the microstructure and tensile properties of ER130S-G low-alloy high-strength steel GMAW additive is studied under different heat input conditions(10.66 kJ/cm,13.34 kJ/cm,15.70 kJ/cm).The results showed that the structure of the additive can be divided into the heated area and the unheated area,the structure of the heated area is mainly composed of acicular ferrite and granular bainite,and the unheated area is mainly composed of thick columnar crystals.With the increase of the heat input,the content of granular bainite decreases,acicular ferrite increases,and some lath martensite appears.At the room temperature,the tensile strength and the elongation after fracture both increase first and then decrease.When the heat input is 13.34 kJ/cm,the mechanical properties are the best,and the tensile fractures are all ductile fractures.