摘要
In this work,ultrasonic energy field assistance combined with tempering treatment is proposed to improve the microstructure and mechanical properties of A517Q alloy steel fabricated by laser directed energy deposition(LDED).The effects of ultrasonic vibration(UV)and tempering treatment on microstructure evolution,microhardness distribution and mechanical properties of deposition layer were studied in detail.The microstructure of UV assisted LDED sample after tempering is mainly composed of tempered sorbite(TS).Due to the improvement of microstructure inhomogeneity and grains refinement,UV assisted LDED sample with tempering treatment obtains excellent mechanical properties.The ultimate tensile strength(UTS),yield strength(YS)and elongation after breaking(EL)reach 765 MPa,657 MPa and 19.5%,the increase ratios of UTS and YS are 14.5%and 33.8%while maintaining plasticity compared to original LDED sample,respectively.It is obvious that ultrasonic vibration combined with tempering is a potential and effective method to obtain uniform microstructure and excellent mechanical properties in metal laser directed energy deposition field.
本工作提出采用超声振动辅助结合回火处理的方法来改善激光定向能量沉积(LDED)A517Q合金钢的显微组织及力学性能。详细研究了超声振动(UV)和回火处理对沉积层的显微组织演变、显微硬度分布和力学性能的影响。经超声振动结合回火处理后的LDED样品的显微组织主要为回火索氏体(TS)。通过改善显微组织的不均匀性及晶粒细化,超声振动同步辅助激光定向能量沉积样品经回火处理后获得了优异的力学性能。其极限抗拉强度(UTS)、屈服强度(YS)和断后伸长率(EL)分别达到765 MPa、657 MPa和19.5%,与原始激光定向能量沉积样品相比,在保持材料塑性的同时,UTS和YS分别增加了14.5%和33.8%。该工作表明超声振动同步辅助结合回火处理是一种在金属激光定向能量沉积领域获得均匀显微组织和优异力学性能的潜在有效方法。
基金
Project(2021YFC2801904) supported by the National Key R&D Program of China
Project(KY10100230067) supported by the Basic Product Innovation Research Project,China
Projects(52271130,52305344) supported by the National Natural Science Foundation of China
Project(ZR2022QE073) supported by the Natural Science Foundation of Shandong Province,China
Project(AMGM2021F01) supported by the Science Fund of Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai,China
Project(KY90200210015) supported by Leading Scientific Research Project of CNNC,China。
作者简介
LI Jian-liang,contributed equally to this work;REN He,contributed equally to this work;Corresponding author:CHEN Zu-bin,PhD,Associate Professor,E-mail:chenzubin@hrbeu.edu.cn,ORCID:https://orcid.org/0000-0001-9120-3310;GUO Chun-huan,PhD,Professor,E-mail:guochunhuan@hrbeu.edu.cn,ORCID:https://orcid.org/0000-0002-2205-2181。
