Effects of different cooling conditions on friction stir processing of A356 alloy: Numerical modeling and experiment

Abstract

In the present work, the effects of in-process cooling are investigated on the material flow, temperature distribution, axial force, wear resistance, and microstructural and mechanical properties of friction stir processed (FSPed) Al-Si aluminum alloy. The finite element method (FEM) was developed for modeling the process, based on the eulerian-lagrangian technique, and then verified by the experimental force and temperature histories. Next, the material flow and temperature distribution during the friction stir process (FSP) with in-process cooling under different conditions were considered. After that, the experimental investigations, including the optical microscopy, hardness, and wear tests, were conducted. Finally, the stir zone (SZ) shape obtained by experiments and simulation model were compared for the FSPed samples without cooling and with air cooling. The material flow achievements reveal that using a coolant affects the material flow in the pin-driven zone more significantly than in the shoulder-driven zone, leading the SZ to change from the basin shape into the V shape. The SZ shapes obtained from the experiments and the simulation model show a good agreement between the shapes of the samples FSPed without cooling and with air cooling. Moreover, experimental results showed that using in-process cooling reduces Si particles' size and thus significantly increases the hardness and wear resistance. The Si particles size is reduced from 10 μm in the base metal to 2.6 μm and 2 μm in the air-cooled and water-cooled samples. Consequently, the wear mass loss reduced almost 28% and 40%, and hardness increased almost 35% and 80% for the air-cooled and water-cooled samples compared to the processed samples without coolant.

Numerical Simulation and Test Study on Track Welding of QTT

“…Te heat input and heat transfer processes during the welding of the azimuth track have a great infuence on both the solid-state phase transition and the microstructure properties. Tis process is a typical nonstationary heat transfer process, and its control equation is [27]…”

“…(3) Te surface heat transfer coefcient between the object on the boundary and the surrounding fuid and the temperature of the surrounding fuid are specifed as follows [27,28]:…”

Preparation of Ti3Si0.8Al0.2C2 Bonded Diamond Composites and Their Friction Properties Coupled with Different Counterfaces

“…Earlier, the authors had successfully fabricated Ti 3 SiC 2 -diamond composites [16], Ti 3 SiC 2 -cBN composites [4], and Ti 3 AlC 2 -cBN composites [17] with 50 wt% of Ti 3 SiC 2 under 4.5 GPa by HPHT. Te high thermal conductivity cBN composites can be synthesized with Al-Si [18][19][20][21] as a binder and diamond as an additive by HPHT [22]. Ti 3 (Al 1−x Si x ) C 2 (x � 0-1) can form a complete solid solution, and the solid solution hardening efect enhances the hardness and corrosion resistance of Ti 3 Al 1−x Si x C 2 [23].…”

Mechanical and wear performance of A356/Al2O3 aluminum nanocomposites by considering the mechanical milling time and microstructural properties

“…and solid-state (powder metallurgy). There are also derivative applications such as hot pressing, compocasting and friction stir process (Çelebi et al , 2018; Bobić et al , 2019; Akbari and Asadi, 2021; Akbari and Asadi, 2022). Powder metallurgy (PM), a solid-state production method, provides low processing temperatures.…”