Evaluation of microstructure and wear behavior of friction stir processed cast aluminum alloy

Microstructure and wear behavior of friction stir processed cast hypereutectic aluminum silicon

“…It is clear that the stirring action of the tool during FSP brings about a significant breakdown of the coarser Si particles and creates a better dispersion of finer Si particles in the stir zone. This is related to thermal exposure and plastic deformation with a strain rate of 100 to 1000 s -1 and strains up to -40 during FSP [2]. The variation of silicon particles of FSPed, and as cast Al-18Si-Cu-Ni samples are presented in Fig.…”

“…Past studies [2,3] reported that Si particle morphology, size, and content, significantly affects the wear resistance of these alloys. The size and morphology of the Si particles are considered to be factors controlling the formation and propagation of cracks [4].…”

“…The size and morphology of the Si particles are considered to be factors controlling the formation and propagation of cracks [4]. Alidokht et al [2] reported that under dry sliding conditions the tendency toward cracking for larger Si particles is greater. It was noticed in [3] that the refinement of Si particles in Al-Si alloys increased the wear resistance.…”

“…It was noticed in [3] that the refinement of Si particles in Al-Si alloys increased the wear resistance. Silicon particles having even and rounded morphology can delay crack nucleation and growth processes in the subsurface region [2].…”

“…Detail explanation of the process if given elsewhere [10]. Previous investigation [11] shows that FSP significantly refined the microstructure of cast Al-Si-Cu-Ni and created a uniform distribution of fine Si particles in the matrix, which is known to be very effective in enhancing wear resistance [2]. Thus, it is important to evaluate the wear behavior of FSPed Al-Si-Cu-Ni.…”