HAMED JAMSHIDI AVAL
Articles written in Sadhana
Volume 44 Issue 1 January 2019 Article ID 0009
The aim of this investigation was to study the effect of tool pin geometry and pass number on mechanical and microstructural behaviour of SiC-incorporated dissimilar friction stir welding of 6-mm-thick plates of AA6061-T6 and AA2024-T351. Two tool pin geometries, square and triangle frustum, were used. Itwas found that the weld made by square frustum pin and two passes with rotation in the same direction produces more homogenized and finer distribution of SiC particles. Also, the grain size of stir zone in the weld made by two passes is finer than that made by one pass. The weld made by triangle frustum pin shows higher thermomechanically affected zone hardness, natural aging kinetics and tensile strength than the others.
Volume 46 All articles Published: 3 July 2021 Article ID 0131
In this research, the friction stir processing passes overlapping effect on AA3105/SiC is studied by evaluating the microstructural, mechanical, and tribological properties of the produced composites. The results indicated that the decrease of offset amount in different passes mediated by the more omogenous distribution of strengthening particles in the processing zone, the composite tensile strength and hardness have increased. The wear rate has decreased by 36%, compared with the sample without the strengthening phase. Also, no significant variations in the hardness, strength, and wear resistance is not seen by the friction stir processing on both sides of the sample. Although, the effect of tool shoulder induced flow is so strong that it restricts the uniform particlemixture and the access of pin-induced flow upwards the stirring region, but the offsetting decrease in the different passes reduces the tool shoulder-induce flow. The obtained highest tensile strength and the lowest wear rate of the fabricated composite equaled to 189.40 MPa and 3.6 x 10-6 gr/m, respectively.