The influence of texture on the bendability in CuNiSi alloys was examined by using an age-hardened polycrystalline strip with various recrystallization textures. In multiple samples manufactured by adjusting conditions of rolling and heat treatment, the Cube orientation f100gh001i, the RD-rotated Cube orientation f012gh100i, the BR orientation f362gh853i and the R(S) orientation f231gh346i, which are the representative recrystallization textures of FCC metals, developed up to 40% in respective area fractions. The bendability was clearly dependent on texture. The sample that had a strongly developed Cube orientation showed the best bendability with respect to both the good and bad ways (GW, BW) in bending. In comparison, the samples in which the BR and the R orientations developed showed poor GW bendability. The sample having a comparably random orientation showed poor GW and BW bendability. The shape of the cracks generated by bending was linear, and these cracks developed in a direction about 40 degrees from the surface. Further, they developed along shear bands, and this result was confirmed by the EBSD measurement. Therefore, the cause of cracking resulting from bending was shear bands. The correlation between the good bendability and a low average Taylor factor was confirmed. More uniform deformation by crystalline slips through texture control was effective for restraining the shear bands, i.e., for obtaining excellent bendability. [

The change in the state of a MgSi cluster with pre-aging at 363 K, followed by aging at 303 or 323 K, was studied by means of a tensile test, three-dimensional atom probe (3DAP), and differential scanning calorimetry (DSC) measurements. MgSi clusters formed during isothermal aging (one-step aging) at 363 K after solution heat treatment were different from the ones formed at 303 and 323 K. Furthermore, during aging at 303 and 323 K following pre-aging at 363 K (two-step aging), the clusters that were originally formed at 363 K (high-temperature clusters) grew in size and a new type of clusters (low-temperature cluster) were newly formed at 303 and 323 K. The increase in yield stress with aging time at 303 and 323 K was greater with the pre-aging at 363 K than without the pre-aging. The greater increase in the yield strength was attributed to the growth of the high-temperature clusters formed in the pre-aging and the nucleation and growth of the low-temperature clusters, both of which proceeded during the aging at 303 or 323 K.

An aluminum alloy hollow extrusion made with a porthole-die has a few seam welds. It is known that the deformation behavior of a weld region is different from that of a non-weld region at room temperature. In the present study, the influence of a seam weld on the high temperature deformation of a 6N01 aluminum alloy extrusion bar was investigated. The elongation of the alloy with the seam weld was significantly lower than that of the alloy without it. This was because the alloy with the seam weld started local necking at a very early stage of deformation. An orientation analysis with an electron backscatter diffraction suggested that a difference in recrystallization texture between weld and non-weld regions would accelerate the start of local necking.

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