PLC控制下激光选区熔化Al-Mg-Mn合金及组织性能研究  

Study on selective laser melting of Al-Mg-Mn alloy under PLC control and its microstructure and properties

作　　者：宋黎明 张大俊 许婄鑫 罗志翔 SONG Liming;ZHANG Dajun;XU Buxin;LUO Zhixiang(College of Electronic Engineering,Zhengzhou Professional Technical Institute of Electronics and Information,Zhengzhou 451450,China;School of materials science and engineering,Zhengzhou University,Zhengzhou 450001,China)

机构地区：[1]郑州电子信息职业技术学院电子工程学院,河南郑州451450 [2]郑州大学材料科学与工程学院,河南郑州450001

出　　处：《粉末冶金工业》2024年第3期106-113,共8页Powder Metallurgy Industry

基　　金：河南省科技攻关项目(212102210530)。

摘　　要：采用基于PLC控制的激光选区熔化成形系统对Al-Mg-Mn合金进行了快速成形,研究了激光扫描速度对成形件致密度、显微组织、物相和硬度的影响,并考察了时效温度和时间对成形件压缩性能的影响。结果表明,随着激光扫描速度从700 mm/s增加至1 300 mm/s,成形试样的孔隙率逐渐上升、相对致密度逐渐减小,平行于沉积方向的熔池逐渐增大、熔合线变细,垂直于沉积方向可见交叉分布的多层沉积熔道,但在激光扫描速度为1 300 mm/s时熔道轮廓较为模糊;在相同激光扫描速度下,平行于沉积方向的平面的硬度要高于垂直于沉积方向的平面;随着激光扫描速度增加,XZ平面和XY平面的显微硬度先增后减,在激光扫描速度为900 mm/s时取得硬度最大值。随着时效温度升高或者时效时间延长,激光选区熔化成形试样的显微硬度、屈服强度和抗压强度先增加后减小,在时效温度为300℃和时效时间为6 h时取得最大值,这主要与此时合金中Al3(Sc,Zr)相的析出强化效果最好有关。The selective laser melting forming system based on PLC control was used for rapid forming of Al-Mg-Mn alloy.The effects of laser scanning speed on the density,microstructure,phase and hardness of the formed parts were studied,and the effects of aging temperature and time on the compression properties of the formed parts were investigated.The results show that with the laser scanning speed increasing from 700 mm/s to 1300 mm/s,the po-rosity of the formed sample increases and the relative density decreases gradually under the condition of other pro-cess parameters unchanged.With the increase of laser scanning speed,the weld pool parallel to the deposition di-rection gradually increases,and the fusion line becomes thinner.Multilayer deposition channels with cross distribu-tion can be seen perpendicular to the deposition direction,but when the laser scanning speed is 1300mm/s,the weld channel contour is relatively vague;At the same laser scanning speed,the hardness of the plane parallel to the depo-sition direction is higher than that of the plane perpendicular to the deposition direction.With the increase of laser scanning speed,the microhardness of XZ plane and XY plane first increases and then decreases,and the maximum hardness is obtained when the laser scanning speed is 90mm/s;With the increase of aging temperature or the extension of aging time,the microhardness,yield strength and compressive strength of the selective laser melting forming sample first increase and then decrease,and the maximum value is obtained when the aging temperature is 300℃ and the aging time is 6 h,which is mainly related to the precipitation strengthening effect of Al(Sc,Zr)phase in the alloy at this time.

关 键 词：工模具钢 粉末冶金 成形工艺 显微组织 应用场景 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG665[金属学及工艺—金属材料]