试样制备对6061铝合金厚板拉伸性能的影响

Effect of Sample Preparation on Tensile Properties of 6061 Aluminum Alloy Thick Plate

以6061铝合金厚板为研究对象,分析了不同取样位置、取样方向、试样直径和过渡弧半径对合金拉伸性能的影响。结果表明,在纵向1/4厚度处切取试样的拉伸性能高于纵向1/2厚度处,与规定塑性延伸强度和抗拉强度相比,断后伸长率对取样位置的敏感度更大。横向拉伸性能比纵向拉伸性能低,尤其是横向拉伸与纵向拉伸的断后伸长率差异较大。拉伸试样平行段直径过小时,合金强度较高,断后伸长率较低;而直径尺寸过大时,由于原始标距的增大,导致计算得出的断后伸长率偏小。过渡弧半径尺寸过小,试样容易在端部附近断裂,断裂位置小于原始标距的1/3,对断后伸长率的影响较大。在试样制备过程中,应严格按照标准中取样位置切取样坯,拉伸试样平行段的直径为8~12 mm、过渡弧半径r≥0.75d0时,合金的拉伸性能具有较高的准确性。

The effect of different sampling positions,sampling directions,sample diameters and transition arc radii on the tensile properties of the 6061 aluminum alloy thick plates was analyzed.The results showed that the tensile properties of the sample cut at 1/4 thickness in the lengthwise was higher than that at 1/2 thickness in the lengthwise.Compared with the plastic elongation strength and tensile strength,the elongation after fracture was more sensitive to the sampling position.The transverse tensile properties were lower than the longitudinal tensile properties,especially the different in elongation after fracture between the transverse and the longitudinal stretching was significant.When the diameter of the parallel section of the tensile sample was too small,the strength of the alloy was higher and the elongation after fracture was lower.When the diameter was too large,the calculated elongation after fracture was small due to the increase of the original standard distance.If the radius of transition arc was too small,the sample was prone to fracture near the end,and the fracture position was less than 1/3 of the original standard distance,which had a great influence on the elongation after fracture.During the sample preparation process,the sampling billet should be cut in strict accordance with the sampling position in the standard,when the diameter of the parallel section of the tensile sample was 8 to 12 mm and the transition arc radius r was≥0.75d_(0),the tensile properties of the alloy had high accuracy.