机械振动对消失模壳型铸造A357合金显微组织和力学性能的影响  

Effect of Mechanical Vibration on Microstructure and Mechanical Properties of A357 Alloy with Lost Foam Shell Casting

作　　者：杨琪琳 王月雷 陈隆波 曾效舒[4] YANG Qi-lin;WANG Yue-lei;CHEN Long-bo;ZENG Xiao-shu(GongQing Institute of Science and Technology,Gongqingcheng 332020,Jiangxi,China;Hainan Vocational University of Science and Technology,Haikou 570100,Hainan,China;Dhurakij Pundit University,Thailand,Krung Thep Maha Nakhon 10700,Thailand;Nanchang University,Nanchang 330000,Jiangxi,China)

机构地区：[1]共青科技职业学院,江西共青城332020 [2]海南科技职业大学,海南海口570100 [3]博仁大学,泰国大曼谷府10700 [4]南昌大学,江西南昌330000

出　　处：《铸造》2023年第12期1607-1613,共7页Foundry

摘　　要：对A357铝合金消失模壳型铸造铸件凝固过程中的机械振动频率如何影响合金的显微组织、力学性能和断裂行为进行了研究。试验结果表明:不同频率下的机械振动显著改善了A357合金α-Al初生相和共晶硅颗粒的尺寸和形貌,提高了A357合金的力学性能和密度。随着振动频率的逐渐增加,A357合金的晶粒尺寸和二次枝晶臂间距逐渐减小,力学性能和密度逐渐提高。α-Al相和共晶硅颗粒的形貌分别由粗枝晶向等轴晶和粗片状结构向纤维状结构演变,振幅越强,平均晶粒尺寸越大,合金的力学性能随着振幅的增加而不断下降。此外,机械振动使A357合金的断口形貌由无振动时的脆性断裂转变为明显的塑性断裂,且随着振动频率的增加,韧窝加深且分布更加均匀。The effects of mechanical vibration frequency on microstructure,mechanical properties,and fracture behavior of A357 aluminum alloy during the solidification process of investment casting were investigated.The results showed that the mechanical vibration at different frequencies significantly improves the size and morphology ofα-Al primary phase and eutectic silicon particles and improves the mechanical properties and density of A357 alloy.With the increasing of vibration frequency,the grain size and secondary dendrite arm spacing of A357 alloy decreased gradually,and the mechanical properties and density of A357 alloy increased gradually.The morphology ofα-Al phase and eutectic silicon particles changed from coarse dendrite to equisetic and from coarse flake to fibrous.The higher the amplitude,the larger the average grain size,and the mechanical properties of the alloys decreased with the increase of amplitude.In addition,the mechanical vibration changed the fracture morphology of A357 alloy from brittle fracture without vibration to obvious plastic fracture,and with the increase of vibration frequency,the dimples were deepened and distributed more evenly.

关 键 词：A357铝合金 消失模壳型铸造 机械振动 显微组织 力学性能 

分 类 号：TG113[金属学及工艺—物理冶金] TG292[金属学及工艺—金属学]