冷轧方式和退火温度对Al-4Cu-0.73Mg合金织构和微观组织的影响

采用硬度测试、X射线衍射(XRD)、电子背散射衍射(EBSD)等方法研究了单向轧制、交叉轧制和退火温度对Al-4Cu-0.73Mg(wt%)合金织构演变和微观组织的影响。结果表明:单向轧制试样在100~300 ℃退火保温1 h后显示出明显的Copper织构{112} <111>、S织构{123} <634>和Brass织构{011}<211>,而交叉轧制试样表现出强烈的Brass织构和H织构{011}<755>。当退火温度高于300 ℃,单向轧制和交叉轧制试样中的变形织构逐渐沿α取向线转变为由P织构{011}<001>、L织构{011}<011>、E织构{111}<110>和R织构{124}<211>等组成的再结晶织构。单向轧制和交叉轧制试样的晶粒尺寸随退火温度的升高先增加后减小,均在350 ℃退火1 h后有最大晶粒尺寸,分别约为8.2 μm和11.5 μm。单向轧制和交叉轧制试样均在冷轧后硬度值最高,约为108 HV,之后硬度值随退火温度的升高而逐渐下降,两种轧制试样的硬度值最终均稳定在50 HV左右。总体来看,轧制方式对试样织构的影响比对力学性能的影响大。

Effect of cold rolling mode and annealing temperature on microstructure and texture evolution of Al-4Cu-0.73Mg alloy

Effects of parallel rolling (PR), cross rolling (CR) and annealing temperature on microstructure and texture evolution of the Al-4Cu-0.73Mg(wt%) alloy were investigated by means of mechanical properties test, X-ray diffraction(XRD) and electron backscatter diffraction(EBSD). The results show that after annealing at 100-300 ℃ for 1 h, the PR specimens show obvious copper{112}<111>, S{123}<634> and Brass{011}<211> textures, while the CR specimens exhibit strong Brass texture and H{011}<755> texture. When the annealing temperature exceeds 300 ℃, the deformation textures in the PR and CR specimens gradually transform into recrystallization textures along α fiber, which consist of P {011} <001>, L {011} <011>, E {111} < 110> and R {124} <211>. The grain size of PR and CR specimens first increase and then decrease with the increase of annealing temperature, and the largest grain size can be obtained after annealing at 350 ℃ for 1 h, which are about 8.2 μm and 11.5 μm, respectively. Both the PR and CR specimens without annealing show the highest hardness values of ~108 HV, which gradually decrease with the increase of annealing temperature and finally are stable at about 50 HV. Overall, the effect of rolling modes on specimen textures is greater than that on mechanical properties.