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Alkali treatment and bioactive glass (BG) sol dip-coating are well-known individual methods for titanium (Ti) surface modification. In this study, a unique combination of alkali treatment and bioactive glass sol dip coating was applied to the Ti substrate, then the mechanical properties and cell responses were investigated. Based on the methods introduced above, the Ti substrate was treated by 6 mL of an NaOH 5 M aqueous solution for 24 h at 60 ̊C; this was followed by adding 1.2 mL of a BG 58S sol to form a novel combined nanostructure network covered by a thin BG layer. For the assessment of the formed coating layer, the morphology, elemental analysis, phase structure, adhesion property and the cell response of the untreated and treated surfaces were investigated. The BG coating layer was reinforced by the nanostructure, fabricated through the alkali treatment. The results obtained by applying the combined modification method confirmed that the mechanical and biological properties of the fabricated surface demonstrated the highest performance compared to that of the unmodified and individually modified surfaces. The achieved upgrades for this method could be gained from the demanded porous nanostructure and the apatite transformation ability of the alkali treatment. Therefore, the hybridized application of the alkali-BG treatment could be introduced as a promising surface modification strategy for hard-tissue replacement applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Annealing after welding is a common operational process to improve the mechanical properties of metallic joints through releasing residual stresses in the weld zone. In this study, the effect of post weld annealing on the microstructure and mechanical properties of dissimilar laser-welds for orthodontic archwires of NiTi alloy to austenitic stainless steel has been investigated. In order to do this, the laser-welded wires were annealed at temperatures of 100, 200, and 300 °C for 1 h and then they were quenched in water. Results show that annealing at 100 °C does not affect the microstructure and mechanical properties of joints but post weld heat treatment at 200 °C ends in an increase in the tensile strength to an order of 1.91 times of the strength of as welded (non-heat-treated) joints. Also, precipitation and increase of intermetallic compounds, such as Cr 2 Ti, and Fe 2 Ti, at the weld zone during heat treatment at 300 °C, results in a reduction in the mechanical properties of joints. Therefore, post-weld annealing is an effective process on improving mechanical properties of dissimilar joints of these two alloys. However, a suitable heat-treatment temperature is needed in order to achieve desired results. Image 1 [ABSTRACT FROM AUTHOR]

Nano-bioceramic particles serving as a reinforcement can improve the mechanical and biological properties of magnesium implants, but they might have some side effects, that must be addressed. In this research, magnesium composites including 10 wt% nano-bioglass (nBG) were fabricated using powder metallurgy (PM10) and spark plasma sintering (SPS10) methods for bone reconstruction purposes. The results of the compression test indicated that the SPS10 sample had higher mechanical properties, in comparison to the PM10 sample, and nBG had more reinforcing effect on the mechanical properties of magnesium matrix. X-ray difractometery indicated that nBG was chemically reacted with magnesium in the PM10 sample, and resulted in some extra phases (MgO and Mg 2 Si) formation, while there was no detectable extra phases in the SPS10 sample. However, a higher in vitro degradation rate was observed for PM10 sample, because of multi-phase formation at the magnesium matrix. To inhibit the chemical reaction between magnesium and nBG kinetically, a short time sintering process can be, therefore, recommended. • The side effect of nano bioglass addition to the magnesium matrix is introduced for the first time. • The time of sintering of Mg-nBG composite, affects its properties. • Magnesium is a high affinity metal and its chemical reactions to reinforcement during processing should be considered. [ABSTRACT FROM AUTHOR]