Study of features of texture and structure evolution during hot rolling in a continuous group of stands of aluminum alloy 6016

Abstract

The article presents the study results of texture and microstructure evolution during automotive 6016 aluminum alloy hot rolling in the multi-stand continuous hot rolling mill. Optical microscopy, scanning electron microscopy, X-ray structure analysis were applied for examinations. 6016 alloy is noted for specific features of structure and texture formation. The peculiarities are due to the high value of the stacking fault energy and a small amount of intermetallic particles of the second phase. The texture in the form of four incomplete pole figures {111}, {200}, {220} and {311} was investigated by the “reflection” method using a DRON-7 X-ray diffractometer in CoKα radiation. When rolling in a continuous group of stands, the coiling temperature level into a coil is 315 oC at a logarithmic deformation of 2.7 and a deformation rate in the last pass of 70 s-1 is insufficient for complete recrystallization during self-annealing. Annealing the hot rolled coil at 425 oC results in a sharp cubic texture. The amount of fine particles in alloy 6016 is very small; therefore, the main mechanism for suppressing recrystallization is an intense recovery process caused by a high stacking fault energy. The specific features are driven by high stacking fault value and low amount of the second phase intermetallic particles. The obtained data could be useful for thermomechanical treatment processes improvement, crystalline texture evolution modelling and 6ХХХ group alloys improvement.The research was conducted on the expences of the Russian Scientific Fund's grant, the project № 21-19-00548, https://rscf.ru/project/21-19-00548/.