轧制方式对6016铝合金薄板组织和塑性各向异性的影响

利用凸耳实验、X射线衍射仪、EBSD等手段研究了热轧退火后常规轧制(NR)、横向轧制(TR)、交叉轧制(AR)等轧制方式对6016铝合金组织和平面各向异性的影响。结果表明:热轧退火后6016铝合金形成了强烈的立方织构{100}〈001〉。NR,TR冷轧板具有38%~44%的β取向线织构(主要包括铜,S,黄铜织构组分),但是AR冷轧后保留了12.2%的立方织构组分,变形织构组分很弱,因此AR冷轧板材制耳率最差,为7.1%。6016铝合金经过固溶处理后,NR,TR板形成9.12%强烈的立方织构,AR板的织构明显弱化且随机分布,因而AR再结晶退火板制耳率较NR,TR板的6%~8.16%明显降低,为2.76%。固溶处理后6016铝合金板的平均晶粒尺寸分别为23,25,22μm,AR轧制后合金的晶粒最小且分布最均匀。因此交叉轧制能有效改善6016铝合金板再结晶退火后的组织均匀性和塑性各向异性。

Effect of rolling mode on microstructure and plastic anisotropy of 6016 aluminum alloy sheet

The effect of rolling mode on microstructure and plastic anisotropy of the Al-Mg-Si alloy sheets was investigated by means of earing test,X-ray diffraction(XRD)and electron backscattered diffraction(EBSD)techniques.The samples were subjected to three cold rolling modes:normal rolling(NR),transverse rolling(TR)and alternate rolling(AR)after hot rolling and annealing treatment.The results show that a strong cube{100}〈001〉texture is formed after hot rolling and annealing treatment of the 6016 aluminum alloy.While the deformation textures significantly vary with the cold rolling modes.A strongβ-fiber textures(copper,S and brass components)is dominant in NR and TR rolled sheets,the volume fraction of which is 38%-44%.In contrast,a cube component with a volume fraction of 12.2%is retained in the AR samples,and the deformation texture component is very weak.Therefore,the AR rolled sheet has the worst earing ratio of 7.1%.After the solution heat treatment,the earing ratio of AR sheets is significantly reduced to 2.76%due to the weak and random texture.While the earing ratio of NR and TR sheets is 6%and 8.16%,due to the same volume fraction of 9.12%strong cube textures.The recrystallized grain sizes of the NR,TR and AR rolled sheets are 23,25μm and 22μm,and the grain distribution of the AR alloy is the most uniform.It is shown that alternate rolling can effectively improve the microstructure uniformity and plastic anisotropy of 6016 aluminum alloy recrystallization sheet.