Search

The combination of aluminum and steel materials in hybrid structures shows promising applications in the automotive, marine, and aerospace sectors. The present study investigates how the tool–pin offset impacts the microstructural, mechanical, and electrochemical characteristics of friction stir-welded joints between dissimilar AA2024-T3 and SS304 materials. The optimum conditions were achieved at a tool rotation of 560 r/min, a traverse speed of 25 mm/min, and a tool–pin offset of 1 mm towards the Al side. Upon increasing the tool–pin offset to 1.5 mm, insufficient heat input resulted in inadequate plastic deformation and material flow, leading to the creation of flaws like voids, tunnels, and interfacial gaps. However, under optimal conditions, the joint exhibited a well-defined and serrated interface, with fine steel fragments securely embedded in the Al matrix. Additionally, thin intermetallic compounds were observed around the steel fragments within the Al matrix. This favorable combination resulted in enhanced tensile strength and increased ductility in the joint. The Vickers hardness test revealed that the stir zone exhibited the highest hardness values, primarily attributed to the ultra-refinement of grains. Furthermore, the potentiodynamic test revealed that the welded samples show improved corrosion resistance against the base material AA2024-T3, although BM-SS304 exhibited the highest corrosion resistance among all the samples, likely due to its higher chromium content. [ABSTRACT FROM AUTHOR]

The current study attempted to introduce nano-aluminium oxide (Al2O3) particles into ZE41 alloy via friction stir processing (FSP). The effect of these nano-Al2O3 particles on the mechanical and tribological characteristics of ZE41 alloy is investigated. The results of microstructural studies revealed the uniform distribution of Al2O3 particles and substantial grain refinement in the stir zone by FSP. Enhanced microhardness was observed in the processed region due to the grain refinement and the occurrence of regularly distributed Al2O3 particles. The wear resistance was also seen increased with the incorporation of the Al2O3 particles. Moreover, the effect of FSP parameters on the successful incorporation of nano-Al2O3 particles in ZE41 alloy without any defect is also realised. [ABSTRACT FROM AUTHOR]

W pracy przedstawiono badania nad zużyciem krawędzi skrawającej wielowarstwowej płytki z ceramiki narzędziowej (TiN/TiCN/Al2O3/TiN) w toczeniu twardym na sucho. Badano także zużycie krawędzi skrawającej w warunkach toczenia na mokro. Nowatorskim rozwiązaniem było zastosowanie mikrokanału w płytce skrawającej, przez który płyn smarny dostarczany jest bezpośrednio do styku między narzędziem i wiórem. Uzyskany tą drogą niższy poziom parametrów skrawania zapewnia minimalne zużycie krawędzi skrawającej, na które w istotny sposób wpływają prędkość skrawania i szybkość posuwu. W porównaniu do warunków toczenia na sucho i na mokro, zastosowanie mikrokanału zmniejsza zużycie krawędzi skrawającej o odpowiednio 48,87% i 3,04%. Narzędzie z mikrokanałem zapewnia także oszczędność zużycia płynu smarnego i energii o ok. 87,5%.

Metal matrix composite (MMC) with matrix material as Zinc-Aluminium alloy ZA-27 and reinforcement as 5% TiC ceramic particles is fabricated in the present study. This MMC is prepared in an electric furnace and subsequently machined on a wire electric discharge machine (WEDM). Taguchi's L27 orthogonal array (OA) is applied with four WEDM parameters: pulse ON time (POT), current (I), pulse OFF time (PFT) and dielectric fluid (DF). To investigate the effect of these parameters on the kerf width (Kw), surface roughness (Ra) and material removal rate (MRR); each of the parameter were individually varied at three different levels. The output responses are analysed using the Entropy-based Measurement of Alternatives and Ranking according to the Compromise Solution (MARCOS) approach. The optimum condition for multiple responses is found at (POT)3 (I)1(PFT)3(DF)2 i.e. pulse ON time at 60 µs, current at 2 A, pulse OFF time at 5 µs and dielectric fluid as vegetable oil. The surface and edge morphology of the machined part is evaluated using SEM micrographs. [ABSTRACT FROM AUTHOR]