Search results for "Materialkemi"
showing 3 items of 3 documents
Room-Temperature Micropillar Growth of Lithium-Titanate-Carbon Composite Structures by Self-Biased Direct Current Magnetron Sputtering for Lithium Io…
2019
Here, an unidentified type of micropillar growth is described at room temperature during conventional direct-current magnetron sputtering (DC-MS) deposition from a Li4Ti5O12+graphite sputter target under negative substrate bias and high operating pressure. These fabricated carbon-Li2O-TiO2 microstructures consisting of various Li4Ti5O12/Li2TiO3/LixTiO2 crystalline phases are demonstrated as an anode material in Li-ion microbatteries. The described micropillar fabrication method is a low-cost, substrate independent, single-step, room-temperature vacuum process utilizing a mature industrial complementary metal-oxide-semiconductor (CMOS)-compatible technology. Furthermore, tentative considerat…
Properties Augmentation of Cast Hypereutectic Al–Si Alloy Through Friction Stir Processing
2022
AbstractThe present endeavour is to augment mechanical attributes via friction stir processing (FSP) in hypereutectic aluminium–silicon castings by the means of microstructural modifications and defects reduction. Wherein, the study proceeds with mainly two approaches namely, alteration in tool revolution (TR) and the number of FSP passes. The prepared specimens were evaluated investigating volume fraction of porosities, microstructural characterizations and microhardness. Therefrom, the specimen with highest number of passes delivered most uniform properties resulting from the reduction in casting porosities and refined silicon particle uniform distribution throughout friction stir process…
Aluminum oxide nucleation in the early stages of atomic layer deposition on epitaxial graphene
2020
In this work, the nucleation and growth mechanism of aluminum oxide (Al2O3) in the early stages of the direct atomic layer deposition (ALD) on monolayer epitaxial graphene (EG) on silicon carbide (4H-SiC) has been investigated by atomic force microscopy (AFM) and Raman spectroscopy. Contrary to what is typically observed for other types of graphene, a large and uniform density of nucleation sites was observed in the case of EG and ascribed to the presence of the buffer layer at EG/SiC interface. The deposition process was characterized by Al2O3 island growth in the very early stages, followed by the formation of a continuous Al2O3 film (2.4 nm thick) after only 40 ALD cycles due to the isla…