Corrosion Resistance Research Articles

Exploring Flower-Structured Bifunctional VCu Layered Double Hydroxide and its Nanohybrid with g-C3N4for Electrochemical and Photoelectrochemical Seawater Electrolysis.

Seawater electrolysis holds great promise for sustainable green hydrogen generation, but its implementation is hindered by high energy consumption and electrode degradation. Two dimensional (2D) layered double hydroxide (LDH) exhibits remarkable stability, high catalytic activity, and excellent corrosion resistance in the harsh electrolytic environment. The synergistic effect between LDH and seawater ions enhances the oxygen evolution reaction, enabling efficient and sustainable green hydrogen generation. Here, we report a synthesis of low cost, novel 2D Vanadium Copper (VCu) LDH first time in the series of LDH's as a highly efficient bifunctional electrocatalyst. The electrochemical (EC) and photoelectrochemical (PEC) study of VCu LDH and VCu LDH/Graphite Carbon Nitride (g-C3N4) nanohybrid was performed in 0.5 M H2SO4 (acidic), 1 M KOH (basic), 0.5 M NaCl (artificial seawater), 0.5 M NaCl + 1 M KOH (artificial alkaline seawater), real seawater and 1 M KOH + real seawater (alkaline real seawater) electrolyte medium. It was found that VCu LDH shows a remarkable lower overpotential of 72 mV hydrogen evolution reaction (HER) and 254 mV oxygen evolution reaction (OER) at current density of 10 mA/cm2 under alkaline real seawater electrolysis exhibiting bifunctional activity and also showing better stability.

Improved Fog Collection on a Hybrid Surface with Acylated Cellulose Coating.

Fog collection serves as an efficient method to alleviate water scarcity in foggy, water-stressed regions. Recent research has focused on constructing a hybrid surface to enhance fog collection efficiency, with one approach being the prevention of liquid film formation at hydrophilic sites. Inspired by the desert beetle, a coating (10-MCC) made by partially acylating microcrystalline cellulose (MCC) exhibits hydrophilic sites alongside a hydrophobic skeleton enabling rapid droplet capture despite its overall hydrophobicity. The captured droplets quickly coalesce into a large droplet driven by the wetting gradient created by the hydrophobic backbone and hydrophilic sites. To achieve greater fog collection efficiency, a hydrophobic-superhydrophobic hybrid surface is formed by combining a coating of 10-MCC with a superhydrophobic surface. The construction of superhydrophobic surfaces typically involves creating a rough surface with a distinctive structure produced by the anodization technique and modifying it with stearic acid. The superhydrophobic surface exhibits excellent corrosion resistance and mechanical stability. Moreover, the hybrid surface shows high efficiency in fog collection, with a tested maximum efficiency of approximately 1.5092 g/cm2/h, 1.77 times that of the original Al sheets. The results demonstrate a remarkable enhancement in fog collection capacity. Furthermore, this work serves as an inspiration for the low-cost and innovative design of engineered surfaces for efficient fog collection.

Investigation on electrochemical corrosion behavior and mechanical properties of Fe-nano particles produced by high-energy ball milling technique

Abstract This study focuses on converting iron particles from grinding sludge, after removing impurities, into Fe-nanoparticles using high-energy ball billing. The goal is to examine the corrosion behaviors and mechanical properties of these Fe-nanoparticles. Nanostructured Fe-powder was synthesized through a process involving 10 h of high-energy ball milling, followed by conventional hot pressing and sintering. Structural and microstructural properties were thoroughly examined using techniques such as X-ray diffraction (XRD), optical microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and elemental diffraction spectroscopy. Upon sintering, SEM and TEM analyses unveiled the formation of a nanostructured alloy within the samples. Notably, the milled sample exhibited high hardness value, measuring at 155 HV. However, it is noteworthy that the un-milled sample demonstrated superior compression strength compared to its milled counterpart. Furthermore, the corrosion behavior of the samples was evaluated through electrochemical corrosion studies. Interestingly, the sample subjected to 10 h of milling (coin number 5) displayed a significantly lower corrosion rate, measuring at 1.3921 mm/year, suggesting enhanced corrosion resistance attributed to the nano structuring process.

Investigation of corrosion resistance and interfacial bonding properties of silver/silicone zinc-rich coating/substrate system in marine environment

This paper aims to study the corrosion resistance and interfacial bonding properties of the silver zinc-rich coating/substrate system and silicone zinc-rich coating/substrate system. The actual working state of the system in marine environment was simulated by the coupled effects of corrosion and pre-stretching. Scanning electron microscope (SEM) with an energy dispersive X-ray spectrometer (EDS) was used in corrosion test to analyze the surface morphology and corrosion products. Meanwhile, the degradation degree of the corrosion resistance was investigated based on the electrochemical impedance spectroscopy (EIS) and water absorption rate. Three-point bending test and tensile test combined with digital image correlation (DIC) were performed to evaluate the interfacial bonding properties of these two systems based on the elastic modulus and critical cracking strain. Results show that the dense accumulation of aluminum and zinc powders makes the silver zinc-rich coating have higher corrosion resistance compared to the silicone zinc-rich coating. The combined effects of corrosion and pre-stretching on the fracture toughness of silicone zinc-rich coating are larger than that of the silver zinc-rich coating. The interfacial bonding properties of the coating/substrate systems gradually degrade as the pre-stretching load approaches the critical cracking load of the coating.

Effect of annealing treatment of hot-rolled AZ31 magnesium alloy on properties and stress corrosion resistance of MAO coatings

Purpose This study aims to study the formation mechanism of micro-arc oxidation (MAO) coating on AZ31 magnesium alloy and how the annealing process affects its corrosion resistance. Design/methodology/approach This study involved immersion experiments, electrochemical experiments and slow strain rate tensile experiments, along with scanning electron microscopy, optical microscopy observation and X-ray diffraction analysis. Findings The findings suggest that annealing treatment can refine the grain size of AZ31 magnesium alloy to an average of 6.9 µm at 300°C. The change in grain size leads to a change in conductivity, which affects the performance of MAO coatings. The MAO coating obtained by annealing the substrate at 300°C has smaller pores and porosity, resulting in better adhesion and wear resistance. Originality/value The coating acts as a barrier to prevent corrosive substances from entering the substrate. However, the smaller pores and porosity reduce the channels for the corrosive solution to pass through the coating. When the coating cracks or falls off, the corrosive medium and substrate come into direct contact. Smaller and uniform grains have better corrosion resistance.

Exploring the effectiveness of negative and positive inserts in machining Inconel 718 alloy: a comparative study

AbstractInconel 718 alloy is characterised by high strength and corrosion resistance and remains stable at high temperatures, so it is widely used in the energy and aerospace industries. However, machining this material is difficult due to its high strength, hardness, and high specific force coefficient exceeding 3000 MPa. Turning of the Inconel 718 alloy can be carried out with negative and positive inserts. Therefore, the impacts of the insert geometry on the turning process of Inconel 718, cutting force components, and surface roughness were studied. Three positive and three negative insert geometries were tested. It was shown that the key influence on the active components of the cutting force is the effective rake angle. The surface roughness, on the other hand, depends mainly on the cutting-edge radius. It has been shown that the negative insert geometry with γ = 6° and rn=22 μm provides a 30% lower cutting force than the positive inserts and the same surface roughness. The developed models of the cutting force components proved that when cutting with positive inserts, a higher specific cutting force occurs for the Inconel 718 alloy than for the negative insert. It was shown that technological parameters had a very similar effect on the cutting force components and surface roughness parameters regardless of the blade geometry. It was proven that the use of positive inserts makes sense only for depths of cut no greater than the size of the corner radius.

Ex-situ Characterization of Nb-Ti Alloy/Pt Coated Stainless Steel Bipolar Plates for Proton Exchange Membrane Fuel Cells

Metallic bipolar plates are crucial for the development of compact and lightweight proton exchange membrane fuel cell stacks; however, most of them encounter durability and conductivity challenges in the fuel cell environment. In this study, Nb-Ti alloy/Pt coatings are deposited on SS316L plates to enhance corrosion resistance, surface wettability, electrical and thermal conductivity, with reduced interfacial contact resistance. Corrosion resistance is assessed by exposing test samples to a 1M H2SO4 acidic environment at 25 °C and 80 °C, respectively, via potentiostatic and potentiodynamic polarization tests. It is found that Nb-Ti alloy/Pt coatings exhibit exceptional stability, with corrosion potential increased by 2.5 (at 25 °C) and 0.5 (at 80 °C) times and corrosion current density reduced by orders of magnitude; and their anti-corrosion performance far exceeds the technical targets set by the US Department of Energy, with a protective efficiency of 99.98 % at both temperatures tested. The coated samples have reduced water affinity, indicated by significantly larger contact angle values compared to the uncoated samples in both pre-and post-corrosion tests. The incorporation of Nb-Ti alloy/Pt coatings on SS316L increases the in-plane electrical conductivity by 42.6 % and thermal conductivity by 3.5 %; surpassing the US Department of Energy's technical targets in these categories as well. At a compaction force of 140 N/cm2, the interfacial contact resistance for the coated samples is about 2.5 times lower than the Department of Energy's requirements. These results indicate the viability of Nb-Ti alloy/Pt coated SS316L bipolar plates for fuel cell applications.

Mechanism Insights in Anticorrosion Performance of Waterborne Epoxy Coatings Reinforced by PEI-Functionalized Boron Nitride Nanosheets.

Functionalized hexagonal boron nitride nanosheets (BNNSs) have arisen as compelling anticorrosive additives, yet the precise mechanism of their corrosion resistance enhancement in coatings remains unclear. Here, polyethylenimine functionalized BNNSs (PEI-BNNSs) with approximately 6-11 layers were prepared through a "one-step" method. Then, the PEI-BNNSs/Waterborne epoxy (WEP) composite coatings were incorporated via the waterborne latex blending method for the anticorrosion of the Q235 substrate. The impedance modulus (|Z|f = 0.01 Hz) of 0.5 wt % PEI-BNNSs/WEP composite coating soaked in 3.5 wt % NaCl solution for 35 days increased by 4 orders of magnitude compared to pure WEP coating, exhibiting exceptional long-term resistance against corrosion. The positron annihilation lifetime spectroscopy and corrosion product analysis demonstrated that the reinforced anticorrosion capabilities are not solely ascribed to the "tortuous path effect" arising from BNNSs impermeability. These mechanisms also encompass the reduction in free volume fraction and radius of the free volume cavities within the composite coating brought about by the PEI molecules. Additionally, the increase in coating adhesion, promoted by PEI, plays an important role in augmenting the barrier properties against corrosive agents. This study provided a full comprehension of the role played by functionalized BNNSs in fortifying the anticorrosion attributes of WEP coatings.

A comparative study of electric current-assisted and conventional sintering of Inconel 718 superalloy

AbstractIn this study, In718 powder mixtures prepared from elemental powders following stoichiometric composition and supplied as a commercial product were produced by conventional powder metallurgy (1300 °C/4 h) and electric current-assisted sintering (ECAS)(1700-2300A/10 min) methods and followed by a double-aging heat treatment. The characterization studies determined that the best results were the sample produced by the ECAS method using the elemental powder mixture. The targeted precipitate γ′, γ″, and δ phases were obtained after the heat treatment, and a hardness value of 344 ± 41 HV0.5 and a relative density of 98.96% were achieved. The sample preserved its surface integrity by exhibiting high corrosion resistance from hot corrosion studies in the temperature range of 650–850 °C and NaSO4 + 60%V2O5 environment. The corrosion rate of the sample, which was subjected to electrochemical corrosion tests in 3.5% NaCl and 10% NaNO3 solutions, was determined as 45.59 mpy and 10.56 mpy, respectively.

Study on the preparation of SiC–C–t‐ZrO2 composites and its corrosion resistance to crushed after‐used lithium batteries

AbstractIn order to solve the severe erosion of kiln refractories for the high‐temperature treatment used during the process of recovering valuable metal elements from waste lithium batteries, this study investigates the low‐cost, no‐firing preparation technology of erosion‐resistant SiC–C–t‐ZrO2 composites with self‐prepared t‐ZrO2–SiC–C powder, as well as silicon carbide and flake graphite as the main raw materials, and phenolic resin as the binding agent. (1) The effects of different t‐ZrO2–SiC–C powder additions and heat treatment temperatures on the properties of SiC–C–t‐ZrO2 composites were studied in details. (2) The erosion resistance of SiC–C–t‐ZrO2 composites to after‐use lithium battery waste was evaluated using the static crucible method. The mechanical properties of the t‐ZrO2–SiC–C composites was the best that its cold modulus of rupture (CMOR) was 11.37 MPa and cold crush strength (CCS) was 41.96 MPa when heat treatment temperature was 600°C and content of t‐ZrO2–SiC–C powder was 10 wt%. At that condition, the bulk density of samples reached to 3.15 g/cm3 and apparent porosity of it was only at 11.09% which means that the samples designed in this work are compacted enough. In the erosion test, the t‐ZrO2–SiC–C composites had an excellent resistance to erosion of lithium battery waste.

Improving the Corrosion Resistance of Micro-Arc Oxidization Film on AZ91D Mg Alloy through Silanization

Improving the Corrosion Resistance of Micro-Arc Oxidization Film on AZ91D Mg Alloy through Silanization

IrO2-ZrO2-SiO2 ternary oxide composites- based DSAs: Activity toward oxygen evolution reaction with long-term stability

BackgroundHigher purity of copper is produced by Electrowinning (EW) in the cathode. A major challenge in this technique is the anodic structure that causes in the energy consumption, corrosion resistance, and contamination of the copper produced in the cathode. MethodsTernary metallic oxide (IrO2-ZrO2-SiO2) composites with the different molar percentages of IrO2: SiO2 (10:60, 15:55, and 20:50%) were prepared on titanium substrate by the sol-gel technique, and then thermal decomposition to study the impact of IrO2 and SiO2 contents on the electrocatalyst performances of the dimensionally stable anodes (DSAs). The physicochemical properties of the DSAs were determined by X-ray diffraction (XRD), Field emission scanning electron microscope (FE-SEM), Atomic force microscopy (AFM), and electrochemical measurements. Significant findingsFE-SEM and AFM images display the impact of SiO2 on the crystallization and crystal growth of IrO2, leading to the formation of finer oxide particles and the porous morphology of the ternary oxide coatings. The DSA composed of 50 % SiO2 and 20 % IrO2 (IZS (20–30–50)) with a more porous surface area represented high apparent electrocatalytic activity toward the oxygen evolution reaction with long-term stability as analyzed under cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and accelerated lifetime (ALT) plots.

Chloride Corrosion Process of Concrete with Different Water–Binder Ratios under Variable Temperature Drying–Wetting Cycles

In this paper, four water–binder ratios (w/b) of 0.29, 0.33, 0.39, and 0.46 were designed. A variable test temperature was implemented in the drying–wetting cycle test according to the temperature fluctuations in the actual service environment, and the constant temperature test was established as the control group. The mechanical properties and chloride corrosion resistance of concrete with different w/b ratios under variable temperature drying–wetting cycles, as well as the microstructure changes, phase composition, and damage mechanism inside the concrete, were investigated. The results showed that the mechanical properties of concrete increased first and then decreased with drying–wetting cycles increasing, whereas the chloride corrosion resistance continued to decline. A higher w/b exacerbated the deterioration of the concrete performance. A higher w/b increased the porosity, chloride diffusion depth, and chloride content, thus reducing the resistance of chloride corrosion. Compared with w/b = 0.29, the compressive strength, splitting tensile strength, mass, and relative dynamic elasticity modulus of w/b = 0.46 exposed to 60 drying–wetting cycles decreased by 54.50%, 52.44%, 0.96%, and 6.50%, respectively, while the porosity, peak chloride content, and erosion depth increased by 45.12%, 70.45%, and 45.00%. Compared with the drying–wetting cycle with a constant temperature, the cumulative damage caused by the drying–wetting cycle with a variable temperature was greater, resulting in more severe deterioration of concrete performance. The increase in the test temperature significantly accelerated the diffusion rate, penetration depth, and chemical binding capacity of chloride ions. After 60 drying–wetting cycles, the peak chlorine content and erosion depth of w/b = 0.46 under variable temperature cycles were 15.38% and 10.32% higher than those under a constant temperature, while the compressive strength, splitting tensile strength, mass, and relative dynamic elastic modulus were reduced by 7.76%, 14.81%, 0.33%, and 2.40%, respectively. Microscopic analysis confirmed that higher w/b and variable temperature cycles accelerated the decay of mechanical properties and the decline of chloride corrosion resistance. According to the numerical fitting analysis, the w/b should be 0.29~0.39 under the condition that the mechanical properties and chloride corrosion resistance of concrete are met.

Nanodiamond Coating in Energy and Engineering Fields: Synthesis Methods, Characteristics, and Applications.

Nanodiamonds are metastable allotropes of carbon. Based on their high hardness, chemical inertness, high thermal conductivity, and wide bandgap, nanodiamonds are widely used in energy and engineering applications in the form of coatings, such as mechanical processing, nuclear engineering, semiconductors, etc., particularly focusing on the reinforcement in mechanical performance, corrosion resistance, heat transfer, and electrical behavior. In mechanical performance, nanodiamond coatings can elevate hardness and wear resistance, improve the efficiency of mechanical components, and concomitantly reduce friction, diminish maintenance costs, particularly under high-load conditions. Concerning chemical inertness and corrosion resistance, nanodiamond coatings are gradually becoming the preferred manufacturing material or surface modification material for equipment in harsh environments. As for heat transfer, the extremely high coefficient of thermal conductivity of nanodiamond coatings makes them one of the main surface modification materials for heat exchange equipment. The increase of nucleation sites results in excellent performance of nanodiamond coatings during the boiling heat transfer stage. Additionally, concerning electrical properties, nanodiamond coatings elevate the efficiency of solar cells and fuel cells, and great performance in electrochemical and electrocatalytic is found. This article will briefly describe the application and mechanism analysis of nanodiamonds in the above-mentionedfields.

In Situ Polymerized Self-Healing Microcapsules as Multifunctional Fillers toward Phosphate Ceramic Coatings.

The protective efficacy of chemically bonded phosphate ceramic coatings (CBPC) is notably diminished owing to the presence of micropores and inadequate self-healing capacity in prolonged corrosive environments. Consequently, it is imperative to augment the corrosion and wear resistance of phosphate ceramic coatings while imbuing them with self-healing capabilities. In this work, a novel self-healing phosphate ceramic coating (MC-PTx@CBPC, x = 0.5, 1.0, 1.5) is designed by urea-formaldehyde (UF) in situ polymerization of nanoscale microcapsules encapsulated with 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFDTES) and evaluated in detail for corrosion and wear resistance. The corrosion inhibition efficiencies of all formulated MC-PTx@CBPC (x = 0.5, 1.0, 1.5) coatings exceed 90%, with the impedance modulus at the lowest frequency (|Z|f=0.01) showing enhancements of 1-2 orders of magnitude compared to pure CBPC. Moreover, the self-healing function becomes active during prolonged immersion. This can be primarily ascribed to the formation of a unique micronanostructure facilitated by nanoscale microcapsules and micrometer-sized alumina ceramics, bonded via the AlPO4 phase. This structure enhances both the hydrophobicity and the bonding strength of the coating. Specifically, following prolonged immersion, the encapsulated PFDTES is liberated from the microcapsules, undergoing hydrolysis and subsequent polymerization upon contact with the electrolyte to form a protective thin film. This film efficiently obstructs the ingress of corrosive agents. Furthermore, the special micronanostructure enhances the hardness of the coating and the releasing PFDTES can form a lubricating film at the interface of abrasion, thus reducing the wear rate and friction coefficient of the MC-PTx@CBPC (x = 0.5, 1.0, 1.5). Therefore, MC-PTx@CBPC (x = 0.5, 1.0, 1.5) possesses excellent corrosion protection, tribological properties, and self-healing capabilities, which provide thought-provoking ideas for phosphate ceramic coatings to protect metals in harsh environments.

Microstructure, Corrosion and Mechanical Properties of Medium-Thick 6061-T6 Alloy/T2 Pure Cu Dissimilar Joints Produced by Double Side Friction Stir Z Shape Lap-Butt Welding

A novel double side friction stir Z shape lap-butt welding (DS-FSZW) process was proposed to achieve excellent mechanical properties of Al/Cu medium-thick dissimilar joints. The influence of welding parameters on weld microstructure and properties of DS-FSZW joint were systematically investigated. It indicated that defect-free medium-thick Al/Cu DS-FSZW joint could be achieved under an optimal welding parameter. DS-FSZW joint was prone to form void defects in the bottom of the second-pass weld. The recrystallization mechanisms at the top and middle of the weld nugget zone (WNZ) were continuous dynamic recrystallization (CDRX) and geometric dynamic recrystallization (GDRX). While the major recrystallization mechanism at the bottom of the WNZ was GDRX. DS-FSZW joint of the optimal welding condition with 850 r/min-400 mm/min was produced with a continuous thin and crack-free IMCs layer at the Al/Cu interface, and the maximum tensile strength of this joint is 160.57 MPa, which is equivalent to 65.54% of pure Cu base material. Moreover, the corrosion resistance of Al/Cu DS-FSZW joints also achieved its maximum value at the optimal welding parameter of 850 r/min-400 mm/min. It demonstrates that the DS-FSZW process can simultaneously produce medium-thick Al/Cu joints with excellent mechanical performance and corrosion resistance.

Modified-TiO2 Nanotube Arrays as a Proficient Photo-Catalyst Nanomaterial for Energy and Environmental Applications

Recently, TiO2 nanotube arrays (TNTAs) have attracted researcher’s attention in the fields of energy production and environmental remediation applications; this is mainly due to their unique optoelectronic characteristics, corrosion resistance, chemical and mechanical stability. In this study, the ability of employing of TiO2 nanotube arrays-based catalysts in the field of photocatalytic CO2 reduction has been investigated. Possible modification strategies have been presented for improving the TNTAs performance by using different types of nanomaterials including graphitic carbon nitrides (g-C3N4), metal-organic frame work (MOF), reduced graphene oxide (RGO) and gold nanoparticles (Au NPs). The TNTAs composites were characterized using XRD and FESEM analyses and the results revealed the successful synthesis of these composites. The TNTAs and their composites exhibited good results for the photo-conversion of CO2 into CH4 gas product. This study gives new ideas for making and developing low-cost Ti metal-based nanomaterials which can be used in the future for recycling the CO2 gas emissions into useful solar fuels.

Tailoring structure, morphology, and tribo-mechanical properties of HiPIMS-deposited CrxNy coatings for enhanced performance in wear and corrosion protection

During reactive sputtering of CrxNy, precise regulation of nitrogen gas is crucial to control the properties of the deposited coating. In the present work, we investigate the influence of nitrogen content on CrxNy characteristics, including morphology, crystalline structure, hardness, corrosion protection, and wear protection performances. Our findings reveal that the hexagonal Cr2N coatings, although slightly lower in hardness (19 GPa) compared to stoichiometric CrN, exhibit superior corrosion resistance with a protection efficiency of 82%, and a reduced sliding wear behavior at 1.35E-09 mm3/N/m. Conversely, stoichiometric CrN shows the highest hardness at 22.8 GPa. Using high-power impulsed magnetron sputtering as a deposition technique, we were able to design CrxNy protective coatings with desired microstructure and phase composition, enabling the production of performance-tailored CrxNy coatings suitable for a diverse range of applications.

Experimental Study on the Performance of Glass/Basalt Fiber Reinforced Concrete Unidirectional Plate under Impact Load

Fiber-reinforced composite materials have emerged as essential solutions for addressing the durability challenges of traditional reinforced concrete, owing to their lightweight nature, high strength, ease of construction, superior tensile capacity, robust corrosion resistance, and excellent electromagnetic insulation properties. This paper delves into the influence of loading rate and fiber bar type on the mechanical characteristics of concrete one-way plates through impact experiments on such plates fitted with glass/basalt fiber bars at varying drop weight heights. The test results reveal a direct correlation between increasing loading rates and escalating damage in fiber-reinforced concrete one-way plates, reflected in the progressive rise in peak deflection and residual displacement at the mid-span of the specimens. Notably, when subjected to higher impact loads, glass fiber-reinforced concrete specimens exhibit amplified deformation and intricate crack formations, consequently diminishing the overall deformation resistance of the plate. Furthermore, glass/basalt fiber-reinforced composites demonstrate notable vibration damping qualities, characterized by substantial residual displacement, minimal rebound, and rapid decay following vibration stimulation. Overall, glass fiber-reinforced one-way plates display marginally superior impact resistance compared to their basalt fiber-reinforced counterparts.

The Influence of Cyclic Thermal Shocks at High Temperatures on the Microstructure, Hardness and Thermal Diffusivity of the Rene 41 Alloy

The precipitation-hardenable nickel-based superalloy Rene 41 exhibits remarkable mechanical characteristics and high corrosion resistance at high temperatures, properties that allow it to be used in high-end applications. This research paper presents findings on the influence of thermal shocks on its microstructure, hardness, and thermal diffusivity at temperatures between 700 and 1000 °C. Solar energy was used for cyclic thermal shock tests. The samples were characterized using microhardness measurements, optical microscopic analysis, scanning electron microscopy coupled with EDS elemental chemical analysis, X-ray diffraction, and flash thermal diffusivity measurements. Structural transformations and the variation of properties were observed with an increase in the number of shocks applied at the same temperature and with temperature variation for the same number of thermal shocks.