不同温度下镁合金挤压棒材组织性能研究

摘要

In this paper,the influence rules of different extrusion temperature on the microstructure,texture properties of ZK60 magnesium alloy are studied.As the extrusion temperature increases,the recrystallization degree of the extruded rod increases gradually.When the extrusion temperature increases from 250℃ to 300℃,the average grain size reduces from 4.21 mm to 3.76 mm and the value of RSD reduces from 1.34 to 1.16,thus the microstructure is homogeneous and refined.When the extrusion temperature further increases to 350℃,the average grain size increases,the uniformity of the organization greatly reduces.At the same time,as the extrusion temperature increases,the texture of interior of the bar is weakened,and the main groups of the texture are divided into ( 0001 ) [ 1010 ] and ( 1120 ) [ 1010 ] .With the comprehensive influence of grain refining,microstructural homogeneity improving and texture weakening at the extrusion temperature of 300℃,comprehensive mechanical property of the extrusion bars is optimal,whose elongation is 26.7％ and tensile strength is 332 MPa,meanwhile yield asymmetry decreases significantly.%研究了不同挤压温度对ZK60镁合金挤压棒材组织、织构及性能的影响规律.随着挤压温度升高,挤压棒材的再结晶程度逐渐增加.当挤压温度由250℃增加到300℃时,棒材的平均晶粒尺寸dm和RSD值分别由4.21μm和1.34减小到3.83μm和1.16,晶粒均匀细小;温度进一步升高到350℃时,平均晶粒尺寸有所增加,组织均匀性大幅降低.同时随着挤压温度不断提升,棒材内部基面织构有所减弱,织构的主要组分为(0001)[1010]和(1120)[1010]织构.在晶粒细化、组织均匀性改善以及织构弱化的作用下,300℃时棒材的综合力学性能最优,伸长率为26.7％,抗拉强度为332MPa,同时拉压非对称性CYS/TYS明显减弱.