Underwater laser directed energy deposition of NV E690 steel  

作　　者：Mingzhi Chen Kun Yang Zhandong Wang Shibin Wang Erke Wu Zhonghua Ni Jinzhong Lu Guifang Sun 

机构地区：[1]School of Mechanical Engineering and Jiangsu Key Lab Design&Mfg Micronano Biomed Ins,Southeast University,Nanjing,211189,China [2]College of Mechanical and Electronic Engineering,Nanjing Forestry University,Nanjing,210037,China [3]School of Mechanical Engineering,Jiangsu University,Zhenjiang,212013,China

出　　处：《Advanced Powder Materials》2023年第3期69-76,共8页先进粉体材料（英文）

基　　金：supported by the fund for the Technical Field of the Basic Strengthening Plan of Science and Technology of a Certain Commission of China(grant number 2021-JCJQ-JJ-0088 and 2022-JCJQ-JJ0117).

摘　　要：Powder-based laser direct metal deposition(DMD),one of the directed energy deposition,was applied in air andunderwater to repair pre-machined NV E690 steel plates.Systematic investigations on the effects of underwaterenvironment and ambient pressures(0.01–0.35 MPa)on the microstructure evolution,phase transformation,andmechanical properties were conducted.The water quenching effect refined the grain size and increased thedislocation density and lath martensite content.The theoretical models of the underwater pressurized nitridingprocess and the precipitation kinetics of(Ti,V)N particles were established.Moreover,the microstructure evolution and the mechanical properties of other underwater DMD repaired samples did not show obvious relationwith the underwater ambient pressures.This investigation not only provides a candidate for the underwaterrestoration technique but also bridges marine engineering and emerging DMD technology.

关 键 词：Laser deposition Microstructure Mechanical property NITRIDING PRECIPITATION 

分 类 号：TG1[金属学及工艺—金属学]