CAJ | 학술논문

利用激光辅助直接金属沉积技术在1018低碳钢上沉积Co-285单壁墙,并利用优化参数制得大面积沉积层.利用光学显微镜、附带能谱仪的扫描电镜、X射线衍射仪、显微硬度计和磨损试验机研究沉积单壁墙或沉积层的显微组织、成分、物相、横截面的显微硬度分布和耐磨性.结果表明:沉积的单壁墙无气孔和裂纹等缺陷,成形性能良好,且与基体形成冶金结合;单壁墙由枝晶和枝晶间共晶组成;所有工艺参数下单壁墙的硬度相差不大;当激光功率为0.8 kW、送粉率为8.6 g/min、扫描速度为0.375 m/min时,单壁墙硬度值最大,达到407HV0.5;在此参数下制得沉积层的组织与单壁墙的类似,其相组成为α-Co固溶体、富Cr的M_(23)C_6和Co_3W;磨损60min后,沉积层体积损失为1.4 mm~3;磨损机制为研磨磨损、粘着磨损和氧化磨损的混合磨损.
이용격광보조직접금속침적기술재1018저탄강상침적Co-285단벽장,병이용우화삼수제득대면적침적층.이용광학현미경、부대능보의적소묘전경、X사선연사의、현미경도계화마손시험궤연구침적단벽장혹침적층적현미조직、성분、물상、횡절면적현미경도분포화내마성.결과표명:침적적단벽장무기공화렬문등결함,성형성능량호,차여기체형성야금결합;단벽장유지정화지정간공정조성;소유공예삼수하단벽장적경도상차불대;당격광공솔위0.8 kW、송분솔위8.6 g/min、소묘속도위0.375 m/min시,단벽장경도치최대,체도407HV0.5;재차삼수하제득침적층적조직여단벽장적유사,기상조성위α-Co고용체、부Cr적M_(23)C_6화Co_3W;마손60min후,침적층체적손실위1.4 mm~3;마손궤제위연마마손、점착마손화양화마손적혼합마손.
The laser-aided direct metal deposition (LADMD) technique was used to fabricate Co-285 single walls on 1018 mild steels, and large scale coatings were fabricated with optimal parameters. The microstructure, composition, phases, microhardness of the cross-section and wear resistance of the deposited single walls or coatings were analyzed by OM, SEM, XRD, microhardness tester and wear tester. The results indicate that the deposited single walls prepared with different parameters are pore and crack free, with good processability. A metallurgical bonding exists between the walls and substrates. The deposited single walls are composed of dendrites and eutectics, and the microhardness under different parameters varies a little, among which the highest hardness is 407HV0.5 when the laser power, powder flow rate and laser scanning speed are 0.8 kW, 8.6 g/min and 0.375m/min, respectively. The coating fabricated with the above parameters has the same structure as the deposited single walls, and the phases are α-Co solid solution, Cr-riched M_(23)C_6 and Co_3W. After wear for 60min, the wear volume loss of the coating is 1.4 mm~3, the wear mechanism is a mixture of abrasive, adhesive and oxidation wear.