Search results for " Corrosion resistance"
showing 8 items of 8 documents
Process parameters and surface treatment effects on the mechanical and corrosion resistance properties of Ti6Al4V components produced by laser powder…
2023
Laser powder bed fusion is one of the additive manufacturing technologies which has developed more rapidly in recent years as it enables the production of very complex geometries. Titanium alloys are among the most popular materials in the aerospace industry thanks to excellent mechanical and corrosion resistance. The corrosion behavior and mechanical properties of samples made of Ti6Al4V and characterized by the geometrical features typical of brackets were investigated taking into account the effects of process parameters on porosity and microstructure. A comparison between the corrosion resistance of samples with complex geometry (3D) and specimens characterized by simple geometry (FLAT)…
Beta forging of Ti-6Al-4V: Microstructure evolution and mechanical properties
2013
Titanium alloys are finding an increasing use in the aeronautical field, due to their characteristics of high mechanical properties, lightness and corrosion resistance. Moreover these alloys are compatible with the carbon fibre reinforced plastics that are also finding a wide use in the aeronautical field. On the other hand the use of these alloys implies some drawbacks, for example titanium alloys are often considered more difficult to form and generally have less predictable forming characteristics than other metallic alloys such as steel and aluminum. In this paper was studied both the microstructure evolution and the mechanical properties of a Ti-6Al-4V rolled bar after hot forging. The…
Effects of anodizing surface treatment on the mechanical strength of aluminum alloy 5083 to fibre reinforced composites adhesive joints
2021
Abstract In this study, the anodizing process based on the use of tartaric sulfuric acid solution (TSA) was carried out on metal substrate to evaluate for the first time its effect on the adhesion strength and corrosion resistance of aluminium alloy (i.e., AA5083) to fibre (i.e., basalt or glass) reinforced composite adhesive joints for nautical applications. Furthermore, some TSA anodized samples were soaked in a NaOH solution to investigate the influence of this post-immersion step on the joint performances. With the aim to improve the fibre-matrix adhesion in the composite substrate thus further increasing the overall mechanical response of the joint, glass and basalt fibres were treated…
The multi-effects of K2TiF6 additive on the properties of PEO coatings on AZ31 Mg alloy
2020
Abstract Plasma electrolytic oxidation of AZ31 Mg alloy was performed in an alkaline silicate-based solution containing various concentrations of K2TiF6 using unipolar waveform at a constant voltage. The surface morphology of all coatings was rough and contained a micro-pore network, micro-cracks, and granules of oxide compounds in different diameters and micro-pore levels. The coating is composed of MgO, MgF2, Mg2SiO4, SiO2 (amorphous), and TiO2 (crystalline and amorphous) phases. The average thickness of the coatings was increased by adding the K2TiF6, where EDS results showed that a skinny fluoride-rich passive layer forms. With increasing time and reaching the final potential, the TiO2 …
CORROSION RESISTANCE OF DIFFERENT STAINLESS STEEL GRADES IN FOOD AND BEVERAGE INDUSTRY
2020
Influence of Centerline Intermetallic Stringers on Pitting Corrosion Resistance of Superduplex Stainless Steel
2021
Superduplex stainless steel UNS S32750 / EN 1.4410 is commonly used in marine environment, petrochemical, oil and gas, chemical and desalination industries, requiring materials with superior corrosion and mechanical properties. Very few residual intermetallic particles may be present under the form of centerline stringers whose effects on corrosion properties are not well documented. A previous study demonstrated the negligible influence of the intermetallic phases in centerline stringers (typically < 0.1% over thickness) on the hydrogen embrittlement susceptibility of superduplex stainless steel [1]. The present study aims at highlighting the impact of centerline intermetallic stringers on…
Effect of Molybdate on Corrosion Performance of Oxide Coating Produced on 7075 Al Alloy Using PEO
2022
In this research, plasma electrolytic oxidation (PEO) coatings were prepared on 7075 Al alloy in a silicate-based solution with Na2MoO4 additive using a unipolar waveform at constant current density. The coatings displayed micro-pores, micro-cracks, pancake-like and crater-like features, and also solidified molten oxide particles on the surface. The coatings were majorly composed of Al2O3 (γ, δ, and α), SiO2 (amorphous), and MoO3 phases, which confirms the incorporation of molybdenum in the case of additive-containing coatings. Molybdenum species were transported through cracks, channels, and micropores, as the ready access pathways into the coating and partly sealed the c…
Silicate and Hydroxide Concentration Influencing the Properties of Composite Al2O3-TiO2 PEO Coatings on AA7075 Alloy
2021
This work evaluates the effect of sodium meta-silicate pentahydrate (SMS) and potassium hydroxide concentrations on properties of Al2O3-TiO2 coatings produced through plasma electrolytic oxidation in a solution containing 3 g L−1 potassium titanyl oxalate, (PTO), using a unipolar waveform with constant current density. The surface and cross-section characteristics of PEO coatings including morphology, elemental distribution, and phase composition were evaluated using FESEM, EDS, and XRD techniques. Voltage-time response indicated the concentration of SMS and KOH had a significant effect on the duration of each stage of the PEO process. More cracks and pores were formed at the higher concent…