AZ31镁合金板材单双杆连续挤压变形过程及组织性能的对比  

Comparison of Deformation Process,Microstructure and Properties of AZ31 Mg Sheet Fabricated by Single and Double Rods Continuous Extrusion

作　　者：赵鸿飞 郭丽丽[1] 赵颖[1] 苑菁茹 运新兵[1] ZHAO Hongfei;GUO Lili;ZHAO Ying;YUAN Jingru;YUN Xinbing(College of Materials Science and Engineering,Dalian Jiaotong University,Dalian 116028,Liaoning,China)

机构地区：[1]大连交通大学材料科学与工程学院,辽宁大连116028

出　　处：《材料导报》2022年第18期119-125,共7页Materials Reports

基　　金：辽宁省自然科学基金(2019-MS-035)。

摘　　要：本工作采用HyperXtrude有限元软件对AZ31镁合金板材连续挤压扩展变形过程进行了数值模拟,研究了单、双杆送料方式对连续挤压过程中板材的温度场、应变场和压力场分布的影响,并对两种进料方式制备的镁合金板材的微观组织及力学性能做了对比分析。结果表明:在3 r/min(63 mm/s)条件下挤压160 mm×8 mm的AZ31镁合金板材时,双杆挤压过程中坯料的应变值小于单杆挤压,由于变形量较小,金属在型腔中的变形温度较单杆连续挤压低10℃左右,且双杆挤压时型腔内的局部压力达到了800 MPa,明显大于单杆挤压。双杆进料条件下板材的平均晶粒尺寸为17.8μm,更细小均匀,平均抗拉强度达到209 MPa,高于单杆挤压的产品,其中间焊缝区域的抗拉强度达到了218 MPa,说明焊合区的性能已超过了母材的性能。In this work,numerical simulations of the continuous extrusion extending forming process were performed for AZ31 magnesium(Mg)alloy sheet by HyperXtrude software.The effect of feeding mode on distributions of the temperature,strain and stress of the sheet during the continuous extrusion were investigated in the single-rod and double-rod extrusion.Additionally,the microstructure and mechanical properties of the extruded Mg alloy sheets were examined under the two feeding modes as well.The results show that when the 160 mm×8 mm AZ31 Mg alloy sheet is extruded under the condition of 3 r/min(63 mm/s),the strain value of the billet in the double-rod extrusion process is less than that in the single-rod extrusion.Consequently,the temperature of the metal in the double-rod extrusion is about 10℃lower than that in the single-rod feeding mode during continuous extrusion.The local stress inside the cavity during the double-rod extrusion reaches 800 MPa,which is significantly greater than that during the single-rod extrusion.The overall average grain size under the condition of double-rod feeding is 17.8μm,which is smaller and more uniform.The average tensile strength of the product obtained by double-rod feeding reaches 209 MPa,which is higher than that of the single-rod extrusion product.The tensile strength of the middle weld zone is 218 MPa,indicating that the property of the welding zone has exceeded that of the base material.

关 键 词：AZ31镁合金 连续挤压 数值模拟 微观组织 

分 类 号：TG376[金属学及工艺—金属压力加工]