高强钢电弧增材制造组织与力学性能研究

Microstructure and Mechanical Properties of High Strength Steel by Wire+Arc Additive Manufactured

利用电弧增材制造技术制备了高强钢薄壁墙试样。分析评价了高强钢电弧增材制造试样的显微组织和力学性能。结果显示:在成型制造过程中有较小的飞溅产生的固体小颗粒,成形外观形貌质量良好;试样金相组织主要为块状和针状铁素体+粒状贝氏体,金相结果可以看出试样内部结构无明显缺陷;试样横向和纵向截面的平均显微硬度分别为321 HV_(0.2),338HV_(0.2),试样的力学性能优良,横向抗拉强度927 MPa,屈服强度829MPa,伸长率16.8%,25℃夏比冲击值51 J,纵向抗拉强度915MPa,屈服强度764MPa,伸长率14.1%,25℃夏比冲击值63 J;拉伸、冲击试样断口形貌图中充满了均匀分布的韧窝,表现为典型的韧性断裂。

Thin wall specimens of high strength steel were prepared by arc additive manufacturing technology.The microstructure and mechanical properties of high strength steel arc additive manufacturing samples were analyzed and evaluated.The microstructure and properties of high strength steel arc additive manufacturing samples were studied.The metallographic structure of the sample is mainly massive and acicular ferrite+granular bainite.The metallographic results show that the internal structure of the sample has no obvious defects.The distribution of microhardness in transverse and longitudinal sections is uniform,and the average microhardness is 321HV_(0.2) and 338HV_(0.2),respectively.The specimen has excellent mechanical properties,with transverse tensile strength 927MPa,yield strength 829MPa,elongation 16.8%,charpy impact value 51J at 25℃,longitudinal tensile strength 915MPa,yield strength 764MPa,elongation 14.1%,charpy impact value 63J at 25℃.The fracture morphology of tensile and impact fracture is filled with evenly distributed dimples,which is typical ductile fracture.