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In-situ pre-decorated different content of TiB2 particle reinforced 2024 Al matrix composites (xTiB2/2024Al composite, x = 0, 1, 2, 4, 6, 8 wt.%) were printed by laser powder bed fusion (LPBF). A quantitative equation was established to quantify heterogeneous nucleating potency by TiB2 nanoparticles on the grain size of the LPBFed samples. Optimized mechanical properties were obtained in the as-printed 4TiB2/2024Al alloy which proved the feasibility of replacing the wrought part with the LPBFed one. This manuscript provides a method to determine the optimized content of TiB2 nanoparticles to change the noncastable material to the printable one. This manuscript provides a method to determine the optimized TiB2 content to change the noncastable material to the printable one, and can potentially guide the introduction of many other nanoparticles.

Many additives are preferred to extend the usage of concrete constructions in order to increase durability. These compounds have to be non-poisonous and have no undesirable consequences on the environs. Out of all these concerns, amino acids are mainly used in food and drug industries as well as safe corrosion inhibitors in a number of acid solutions. Here, the corrosion inhibition efficacy of optimum concentration (50 ppm) of caffeine and L-arginine has been investigated for reinforcement steel in mixture water (MW) environment. This was performed for a duration of 2 h, 7, 28, 56 and 90 d using electrochemical impedance spectroscopy (EIS), dynamic EIS (DEIS), and potentiodynamic polarization (PDP) techniques. The surface of specimens was also investigated by atomic force microscopy (AFM), optical profilometer (OP) and scanning electron microscopy (SEM). DEIS results indicate that selected inhibitors protected reinforcement steel approximately up to 62% against corrosion till 7 d, then the effectiveness of the protection decreased to 30% on 90th day. It was also observed that L-arginine showed better inhibition efficiency than caffeine. Duzce University Research FundDuzce University [2019.06.05.1036] The authors acknowledge the financial support provided by the Duzce University Research Fund (Project No: 2019.06.05.1036). The authors also thank Dr. Marziya Rizvi (ORCID ID: 0000-0001-8928-529X) for his assistance in the interpretation of the EIS measurements. Africa Centre of Excellence in Future Energies and Electrochemical System, Federal University of Technology, Owerri, Nigeria is acknowledged for their contribution to this study. WOS:000650506200001 2-s2.0-85106258076

In previous work, we have established a scheme that exploits a three-dimensional heat and mass flow model to assess tool durability and define the domains of satisfactory tool life in the context of welding difficult aluminium alloys. We now apply this scheme to the friction stir welding of steel and extend the calculations to cover consequences on the microstructure of the steel while optimising tool life. This is the first published model that covers both the processing parameters and the consequences on the physical metallurgy of the steel.

Spray formed billets of Al-4Li-0 center dot 14Zr (wt-%) were processed by a combination of hot isostatic pressing (HIPing), homogenisation, and solution treatment and aging. Extensive oxidation damage occurred after homogenisation in air, but could be alleviated by using controlled atmosphere or by prior HIPing. The microstructure and tensile properties were studied at various stages of processing. The volume fraction of AlLi (delta) decreased successively after HIPing, homogenisation and T6 temper, redistributing itself towards grain boundaries. The Al(3)Zr (beta') phase was absent in the as formed condition, but precipitated after HIPing at 838 K/4 h and/or stepped homogenisation finishing at 838 K/4 h. Room temperature tensile properties were poor in the as spray formed condition, but improved after HIPing, homogenisation and T6 treatment successively. The tensile properties of the alloy were also evaluated between 648 and 848 K, for preliminary identification of optimum hot working parameters. HIPing did not affect high temperature yield strength significantly, but increased the ductility.