16/10/2020
a map of the distribution of Meyer microhardness (H), Young's modulus of elasticity (E), and their ratio, which makes it possible to identify the nanostructure in the macrostructure (H / E more than 0.04) of a weld got by friction stir welding in Instytut Spawalnictwa, Poland.
WHY IS IT IMPORTANT?
As we know, the idea of using the unique properties of nanoparticles is the main concept of nanoscience for creating innovative dispersion-hardened materials and its constructions.
So the nano-mechanical description in detail of the stirred zone allows us to optimize the welding mode - the number of revolutions in place depending on the linear welding speed along the joint. Taking the average of stirred to nanosized Al-alloy grains as 100 nm and the average grain diameter of basic polycrystalline aluminum as 100000 nm (0.1 mm), the scale ratio is 1: 1000. Consequently, grain refinement (inverse proportion) will occur at 3-4 revolutions of the FSW tool in one place. Therefore, the grinding of grain will occur at 3-4 rotations of FSW tool in one place:
1 turn – 1597, 987, 610, 377,
2 turn – 233, 144, 89, 55,
3 turn – 34, 21, 13, 8,
4 turn – 5, 3, 2, 1.
published by:
1) К. Krasnowski, Yu. Khokhlova, M. Khokhlov. Influence of tool shape for friction stir welding on physicomechanical properties of zones of welds of aluminum alloy EN AW 6082-T6. Paton Welding Journal, International Association "Welding". ISSN 0957-798X, Issue 7, July 2019, P. 7-11. https://doi.org/10.15407/tpwj2019.07.02
2) Хохлова Ю.А., Ищенко Д.А., Хохлов М.А. Индентирование от микро- до нанометрового уровня и примеры исследования свойств материалов с особой структурой. Техническая диагностика и неразрушающий контроль. - №1. 2017 – с. 30-36.