Reduced Service Life Research Articles

Study on the water and mold resistance of ZnO/polyurethane superhydrophobic coating on circuit boards

In this work, superhydrophobic coatings were prepared on circuit boards based on the susceptibility of circuit boards to harsh environments such as humidity and mold adhesion, leading to reduced service life. Firstly, cetyltrimethoxysilane and γaminopropyltriethoxysilane were used to modify zinc oxide nanoparticles with different particle sizes. Then polyurethane and modified nanoparticles were successively sprayed on the circuit boards with a spraying process, and the superhydrophobic coatings were finally produced. The impact of the zinc oxide mass ratio with different particle sizes, silane coupling agent content, and surface modifier content on the hydrophobicity of the coatings were investigated. The results show that when the mass ratio of zinc oxide (30nm) to zinc oxide (90nm) is 1:1, the silane coupling agent content is 12‰. The surface modifier content is 12‰, the hydrophobicity of the coating is the best, and its CA can be up to 169.5°, and its SA can be up to 2.8°. It exhibits good protection of circuit boards in the tests of adhesion, acid, and alkali corrosion resistance, self-cleaning performance, and anti-mold performance. Performance, so that the coating is in the future field of electronic equipment applications.

Metal-organic framework-derived in situ-grown Cu2Sb@NC octahedra for high-performance stable lithium/sodium storage

Intermetallic compounds are considered a special class of alloy-type anode materials that show great potential for use in lithium/sodium-ion batteries due to their inherent advantages, such as high specific capacity and enhanced safety features. However, their practical application is often impeded by the substantial volume changes that occur during the insertion and extraction of Li+/Na+ ions, leading to capacity decay and reduced service life. To address this challenge, we developed a novel composite material comprising Cu2Sb nanoparticles encapsulated within a N-doped octahedral carbon matrix (Cu2Sb@N-C). This composite structure features a heteroatom-doped conductive network, a three-dimensional carbon framework, and finely dispersed Cu2Sb nanoparticles. Benefiting from the heteroatom-doped conductive network, three-dimensional carbon framework and ultrafine Cu2Sb nanoparticles, they not only provide a penetrating network for the fast transfer of charge carriers and improve the accessibility of ions, but also alleviate the agglomeration and volume expansion of Cu2Sb during cycling. For LIBs, the material exhibited a reversible capacity of 1001.0 mAh/g after 330 cycles at 0.2 A/g, while maintaining a substantial capacity of 565.5 mAh/g after 1000 cycles at 1.0 A/g. In the case of SIBs, the material exhibited a capacity of 375.6 mAh/g after 100 cycles at 0.2 A/g. Post-cycling electrode analyses revealed that the Cu2Sb@N-C anode material retained its structural integrity, demonstrating its ability to withstand the continuous insertion and extraction of Li+/Na+ ions. This research contributes insights into the effective design of innovative high-capacity alloy-based anode materials for advanced secondary batteries.

Investigation on the restoration properties of wood oil microcapsules in wood coatings

Wood coatings endure wear and tear and may experience reduced service life. Therefore, the self-healing feature is crucial for practical application in wood protection. The study involved preparing a self-healing microcapsule through in-situ polymerization. Wood oil was utilized as the core material and urea-formaldehyde resin (UF) as the wall structure, forming a “core-shell” structure. The average particle size of the microcapsules is approximately 2.8 μm. Wood oil Microcapsules of varying content are added to water-based coatings and applied to form a self-healing wood coating. When external forces damaged the wood coating, the microcapsules ruptured and released the inner core to repair the coating. The study results indicated that adding microcapsules at a 6 % level significantly increased the coating's repair rate to over 30 %, enhancing its mechanical properties. This microcapsule type in wood oil can protect wood coatings and guide future wood coating repair methods.

Insight into the corrosion inhibition mechanism of mild steel St1 in 2 M H2SO4 electrolyte by azithromycin

Mild steel is essential in modern industry due to its favorable mechanical properties and economic availability. However, its high susceptibility to corrosion, especially in acidic environments, poses a significant challenge, reducing service life, increasing operating costs, and raising the risk of failures. This study investigates the corrosion inhibition mechanism of mild steel St1 in a 2 M H2SO4 solution at various temperatures using the broad-spectrum antibiotic azithromycin (AZM). Experimental results indicate that AZM presence increases the polarization resistance of mild steel in the acidic solution. AZM acts as a mixed-type inhibitor, influencing the kinetics of both cathodic and anodic processes. The introduction of 200 mM AZM leads to an increase in the polarization resistance of the steel electrode in 2 M H2SO4 by up to 2.4 times. The inhibition mechanism involves forming a protective layer of protonated AZM forms on the negatively charged Fe surface. These protonated forms can also adsorb on cathodic areas, competing with hydronium ions (H3O+) and thereby inhibiting hydrogen evolution processes. The protective effect of AZM diminishes with increasing temperature of the corrosive environment, as confirmed by Monte Carlo simulations showing decreased adsorption energies for AZM and its protonated forms at higher temperatures. An assessment of the protective effect of 200 mM AZM showed that an increase in the temperature of the corrosive environment from 293 to 333 K leads to a decrease in the protective effect by almost 5.6 times. Quantum chemical calculations determined the reactivity of AZM and its protonated forms, identifying the molecular groups involved in the adsorption mechanism.

A stacking sequence optimization strategy for process‐induced deformation of multi‐layer thick asymmetric laminates

AbstractThe occurrence of process‐induced deformations of composites laminates is challenging for assembly accuracy and may lead to a service life reduction of parts. However, it can be obviously mitigated through different optimization strategies on the basis of the accurate curing process simulation. In this study, a stacking sequence optimization strategy is proposed and applied to multi‐layer thick asymmetric laminates. The shapes of deformed laminate plates are experimentally investigated in virtue of the three‐dimensional coordinate measuring machine. The thermo‐chemical–mechanical behaviors of plates are first verified through the comparisons of model predicted and experimental process‐induced deformations. Then the nonlinear control formula achieved through the regression model is proposed for the direct relationship between stacking sequences and process‐induced deformations. Finally, the required solutions are generated by solving the control formula. With the comparisons between the average deformations before and after optimizations, it is found that the magnitudes of deformations are significantly reduced, especially when the unoptimizated deformations are large.Highlights The thermo‐chemical–mechanical behavior can be described in the curing process simulation model. The deformed shapes of multi‐layer thick asymmetric laminate plates are measured by a three‐dimensional coordinate measuring machine. The stacking sequence optimization strategy is implemented by introducing a nonlinear control formula.

Waterborne polyurethane based on dual crosslinked structure with excellent mechanical properties, water and corrosion resistance

Due to the increased presence of hydrophilic groups in waterborne polyurethane (WPU) coatings, consequently leading to compromised corrosion resistance and reduced service life. To solve the problem, a series of waterborne polyurethanes were synthesized via internal emulsification using dicyclohexylmethane diisocyanate (HMDI) and polytetrahydrofuran ether diol (PTMG) as the primary raw materials. The triethanolamine (TEOA) was used as a crosslinking agent and corrosion inhibitor, while N- (β-aminoethyl) -γ-aminopropyl trimethyl-(ethyl) oxy-silane (KH-792) was introduced as a coupling agent to establish a system with a dual crosslinking structure. The crosslinking degree of the double network structure can be adjusted by changing the amount of KH-792. Then the influence of KH-792 content on the performance of SWPU dispersions and film were studied. The research shows that the waterborne polyurethane with a KH-792 content of 3 wt% exhibits exceptional mechanical strength, reaching 34.64 MPa, with only 3.32 % water absorption and an adhesion strength of 2.64 MPa. Furthermore, it exhibited a high impedance modulus (2976.4 Ω/cm2) at low frequencies. Therefore, this compound holds promising potential for application in anti-corrosion coatings field.

Insights into different marine aquaculture infrastructures from a life cycle perspective

Aquaculture facilities represent an often-neglected process in environmental impact studies. This study focus on the environmental impact assessment of alternative net materials in Mediterranean marine aquaculture. A Life Cycle Assessment was conducted using primary and secondary data from specific databases and literature. Three baseline scenarios were compared: copper alloy net cages with 100 % of recycled material (CAN100), 75 % of recycled material (CAN75), and polyethylene net (PEN) System boundaries include manufacturing and disposal of cages, nets, and mooring system. The use and emissions of antifouling paints and CAN were considered. Sensitivity analysis of the most impacting sub-processes and Uncertainty analysis were also conducted. The use of CAN is advantageous in terms of environmental impact, but only considering a complete recyclability of the net at the end of its service life. Moreover, when considering a reduced service life of the PEN due to the detrimental effect of biofouling, the advantage of the CAN is even more evident. To counteract the negative effect of biofouling, copper-based antifouling paints are generally used in marine aquaculture. These products are a main environmental hotspot in PEN systems. Therefore, a higher consumption of such products could determine an environmental burden shifting from CAN to PEN ones. So far, CAN are not widespread in the aquaculture industry, mainly due to the high cost of initial investment compared to traditional PEN. Considering operational and environmental advantages, CAN cages could represent an affordable and resilient solution for aquaculture enhancing environmental, economic, and social performances of this industry.

Numerical investigation of bucket wear and excavation performance with non-spherical materials

Wear significantly affects equipment performance at mining sites, especially when excavating materials with diverse shapes, leading to increased bucket wear and reduced service life. This work combines the co-simulation of multibody dynamics and discrete element method with the Archard wear model to investigate the dynamic interactions between the bucket and non-spherical materials, and the impact of bucket wear on excavation performance. The results indicate that wear is evident on the bottom surface, side surface, and teeth of the bucket throughout the working cycle. The wear patterns observed for different teeth vary, highlighting the importance of maintenance for the middle and side teeth. Compared to spherical particles, ellipsoidal ones cause greater excavating resistance, bucket wear, and hydraulic fluctuations. As wear intensifies, the teeth become blunt, and the bottom surface exhibits unevenness, resulting in reduced payload and increased resistance and hydraulic power. Proposed wear mitigation strategies can help uphold satisfactory operating performance.

Thermal management of lithium-ion battery modules optimized based on the design of cold plate with convex pack structure

To address the issue of temperature increase in battery modules using liquid cooling plates, a convex pack structure within the flow channel is proposed to enhance flow efficiency. High temperatures can lead to battery performance deterioration, increased safety risks, and reduced service life. The optimal parameters for the convex structure (radius, transverse spacing, and longitudinal spacing) were determined through simulation analysis and orthogonal experiments. The effects of discharge rate, ambient temperature, coolant inlet temperature, and inlet speed on the heat dissipation of the battery module were also studied. The results show that the convex pack structure enhances heat transfer by increasing the contact area and fluid velocity while inducing eddy currents to achieve lateral mixing. The optimal parameters were found to be: radius (r) = 0.75 mm, horizontal spacing (x) = 3.50 mm, and vertical spacing (y) = 4.50 mm. At low discharge rates, the battery performs well, but high discharge rates negatively affect temperature uniformity. An increase in ambient temperature raises the temperature difference and maximum battery temperature. Lower coolant inlet temperatures reduce the maximum temperature but may result in uneven temperature distribution. Achieving a balanced coolant flow rate is essential to minimize temperature variations and control pressure buildup. This research introduces an innovative heat transfer structure, the convex pack, which significantly improves cooling efficiency. Further research on enhanced heat transfer structures is necessary to continue advancing cooling technologies for battery modules.

Study of the thermal state of the transformer depending on the operating mode

Accurate analysis and prediction of the transformer's thermal condition depending on the operating mode, for example, in cold winters with a shortage of electricity, allows for effective planning of regular maintenance. In the course of the work, mathematical models were created to analyze the thermal state of the transformer, in particular, models for finding the temperature of the upper layers of oil and the highest temperature on the transformer winding. The data from these mathematical models were verified by comparing them with an already identified analog model. It was determined that the difference between the results is no more than 7 %. It has been established that the thermal state of the transformer is influenced by the ambient temperature much more than by the load. This is due to the fact that without cases of overload and emergencies, the load on the transformer, depending on the season, does not change significantly. It has been determined that the highest time utilization and the highest temperature on the high and low voltage windings are observed in August, which coincides with the peak ambient temperature. The lowest temperature on the windings and the lowest life utilization of the transformer are observed in January, which also correlates with the lowest ambient temperature. It is determined that under such operating conditions, given that the nominal service life of the transformer is 20 years, the actual service life will be approximately 90 years. It was also found that the reduction in service life in winter is 5 times less than in summer. This allows us to predict a reduction in maintenance needs during the cold months and more intensive maintenance in the summer. In addition, such models can predict potential problems and emergencies, which can significantly reduce the risk of unforeseen outages and increase the reliability of power supply. Regular monitoring and analysis of the thermal condition of the transformer makes it possible to respond quickly to changes in operating conditions and make timely maintenance decisions, which helps to optimize costs and increase the efficiency of power grids.

Lok-Test and Capo-Test pullout for in-situ concrete strength

Among the test systems for in-place concrete strength available today, two measure the in-place physical strength, pullout, and cores. Both systems are dealt with in detail in this paper, the pullout systems named LOK-TEST/CAPO-TEST (ASTM C900-19) and coring (ASTM C42/42M-18). Testing in-situ with accurate test systems will reveal effects on the final strength from a potential mix’s over transportation, pumping, consolidation, compaction, and curing. With the LOK-TEST system testing of the pre-installed inserts takes 4–5 minutes each, easily and with only one small suitcase brought along. The CAPO-TEST, originally designed to supplement the LOK-TEST, takes 15–20 minutes for each test to be performed anywhere on a structure without pre-installed inserts. No large holes are left in the structure from coring and thinner elements may be tested without weakening them structurally. The pullout test provides accurately the In-Place Strength without testing cores and the duration is about 15 minutes compared to 3–4 days for coring correctly cured. General robust correlations to strength of standard specimens exist no matter what parameter is considered for normal concrete, even for carbonation of the surface layer. With the systems the cover layer protecting the reinforcement may be checked efficiently and quickly, not at least in areas with dense reinforcement or on slim structures. Bad curing conditions are revealed and the consequences in terms of reduced service life for presence of chlorides or carbonation may be estimated swiftly. This paper is benchmarking 50 years of successful in-situ concrete strength measurements, from studies of the failure mechanism and laboratory/on-site correlations to full scale testing of structures in Europe, Scandinavia, and Canada. Six testing cases with emphasis on pullout and cores are illustrating different applications: Case 1. Production testing at the Great Belt Link, Denmark. Case 2. Service life of bridge pier, Great Belt Link, Denmark. Case 3. Curing of the cover layer evaluated by pullout and conductivity, Denmark. Case 4. Strength testing with CAPO-TEST for further loading of old bridges, Poland. Case 5. In-Situ compressive strength testing of quarantined precast concrete tunnel lining segments using CAPO-TEST, UK. Case 6. Safe and early loading with LOK-TEST, Canada. Other cases are given on www.NDTitans.com

Comparative analysis of the effectiveness of passive and active filters of higher harmonics as part of the electrical complex of metal heat treatment

The presence of a nonlinear load connected to the power supply network causes a distortion of the sinusoidal shape of the current and voltage curves, resulting in higher harmonics. Higher harmonics lead to overloading and overheating of equipment, reduced reliability and reduced service life, and can have a negative impact on the quality of electricity. As part of the task of ensuring the reliability of power grids, an important task is to control the level of harmonic components and use special devices to minimize their impact. To combat higher harmonics in power grids, various devices have been developed and used, including line chokes, passive filters, and active filters. The choice of a particular device depends on the parameters of the power grid, the type and characteristics of the connected load, the level of harmonic components, and the requirements for the quality of electricity. Linear chokes are capable of reducing the level of harmonics in the power grid, but, having a number of disadvantages, require additional justification when deciding on their use. A passive filter has a circuit consisting of a choke, resistor, and capacitor, can have different configurations, and is tuned to the frequency of a specific harmonic to suppress its effects. Passive filters are more effective in combating higher harmonics generated by nonlinear noise, more economical and easier to maintain, but have a limited frequency range, fixed parameters and significant weight and dimensions, which limits their use. Active filters include active components to generate signals that are out of phase with harmonic components, thus compensating for higher harmonics. Active filters are more flexible, capable of correcting distorted and shaped signals, are much more efficient than chokes and passive filters, but are less cost-effective and more power-consuming. In the presented work, a passive six-link LC filter and a shunt active filter based on the principle of instantaneous compensation of active and reactive currents are investigated. In the active filter, harmonic distortion compensation is provided by a proportional-integral controller. In this paper, we have carried out simulation modeling of passive and active filters as part of an electrical complex for metal heat treatment and analyzed the results of harmonic distortion compensation

Study of corrosion resistance of superhydrophobic hydrotalcite cement mortar in chlorine salt environment

Reinforced concrete structures are susceptible to reduced service life owing to the erosion caused by the of chlorine-containing, external environment and internal chloride. In this paper, a superhydrophobic hydrotalcite cement mortar was studied with internal and external cooperation against chloride ion erosion. The effect of different hydrotalcite substitution amounts on the chlorine corrosion resistance of the mortar was investigated. The mortar exhibited good resistance to chlorine corrosion, and the corrosion resistance rate increased by 91.83 %. The free chloride ion concentration measurement and rapid chloride migration test exhibited that the prepared mortar effectively resisted chloride ion invasion and reduced the content of free chloride ions in the mortar. The proposed anticorrosion method is expected to have potential application prospects for concrete structures under chloride salt environments.

Quality of hydraulic hoses with reduced service life

The impact of using rubber hydraulic hoses with a shortened service life on environmental pollution has not yet been raised in the scientific national literature. Most researchers focus on the analysis of used engine oils or contaminated fluid in hydraulic systems, rather than on their direct environmental impact. For some time now, the European market has seen an increase in imports of cheap rubber hydraulic hoses from countries outside the Community. There is a potential risk of negative environmental impacts from the use of these hoses if they do not meet appropriate quality standards. The study examined samples of hydraulic hoses purchased directly from the manufacturers or traders of rubber hydraulic hoses from countries outside the European Union. The products were tested for compliance with PN-EN 853:2015-05 and PN-EN 857:2015-05. Out of 14 fully tested hydraulic hoses, only 2 were found to comply with the applicable European standards. The results encourage further research to determine the impact of rubber hydraulic hoses with reduced service life on environmental and economic costs.

Study on Flat Die Wear Characteristics in Flat Die Pelletizing with Different Material Ratios Based on DEM-FEM

Wear can occur in flat die pelletizers, often reducing service life. This study explores the issue of die hole wear in the pelletizing process of a standard Total Mixed Ration (TMR) feed. The selected TMR formulation comprises varying proportions of corn, alfalfa hay, and quinoa. A coupled DEM-FEM analysis was used to examine stress–strain conditions in various die hole regions at different material ratios, predict the fatigue life of flat die materials in the pelletizing process, and validate the accuracy of investigating flat die wear through friction wear tests. It was found that the entrance of the die hole experiences the most severe conditions in terms of equivalent stress and elastic strain. The fatigue life is shortest at the entrance, with a maximum equivalent stress of 42.8 MPa, a maximum equivalent elastic strain of 2.5 × 10−3, and a minimum fatigue life stress cycle of 5.0 × 105. In contrast, the equivalent stress and equivalent elastic strain at the middle and upper parts of the die hole are minimal, with an equivalent stress of 4.8 MPa and a minimum equivalent elastic strain of 2.8 × 10−4. Material wear tests revealed that the most severe wear on the flat die specimen occurred when the ratio of corn, alfalfa hay, and quinoa straw was 7:2:1, consistent with the findings from the DEM-FEM coupling method. The pelleting process, arising from the contact between the material and metal, encompasses adhesive wear, abrasive wear, and fatigue wear.

Weather effects on the lifecycle of U.S. Department of Defense equipment replacement (WELDER)

Extreme weather has a direct and significant impact on buildings and infrastructure, resulting in billions of dollars of damage each year. This problem continues to grow as climate patterns change and buildings are exposed to new and different hazards than what they were designed to withstand. In order to better plan for the long-range sustainment, restoration, modernization, and eventual recapitalization of these buildings, organizations with large building portfolios, such as the U.S. Department of Defense (DoD), must have an awareness of the risks that these extreme weather events present. This research aimed to develop an approach to estimate condition loss and reduction in service life for the components of a building due to extreme weather hazards, to understand the risks that may be present in certain buildings and building systems. To achieve this objective, a damage association matrix was developed that categorizes climate hazards, the damage modes that they produce, and the individual component types impacted. This damage matrix formally links state-of-the-art climate model output, which provides projections of the probability of various climate hazards with a damage effects model that quantifies the consequence on component-level condition and service life. This method is applied to an actual portfolio of buildings in a particular geographic location and with a pre-defined component inventory that comprises the building. This approach can be aggregated to the system-, facility-, and site-level thus helping support billions of dollars in recapitalization decisions related to restoration/modernization of facilities.

Research Enhancing Acidic Mine Wastewater Purification: Innovations in Red Mud-Loess.

This study investigates the adsorption of cadmium (Cd) by red mud-loess mixed materials and assesses the influence of quartz sand content on permeability. Shear tests are conducted using various pore solutions to analyze shear strength parameters. The research validates solidification methods for cadmium-contaminated soils and utilizes SEM-EDS, FTIR, and XRD analysis to elucidate remediation mechanisms. The findings suggest that the quartz sand content crucially affects the permeability of fine-grained red mud-loess mixtures. The optimal proportion of quartz sand is over 80%, significantly enhancing permeability, reaching a coefficient of 6.7 × 10-4 cm/s. Insufficient quartz sand content of less than 80% fails to meet the barrier permeability standards, leading to a reduced service life of the engineered barrier. Adsorption tests were conducted using various pore solutions, including distilled water, acidic solutions, and solutions containing Cd, to evaluate the adsorption capacity and shear characteristics of the red mud-loess mixture. Additionally, the study examines the behavior of Cd-loaded red mud-loess mixtures in various pore solutions, revealing strain-hardening trends and alterations in cohesiveness and internal friction angle with increasing Cd concentrations. The analysis of cement-red mud-loess-solidified soil demonstrates enhancements in soil structure and strength over time, attributed to the formation of crystalline structures and mineral formations induced by the curing agent. These findings provide valuable insights into the remediation of cadmium-contaminated soils.

Study on moisture absorption characteristics of glass fibre‐reinforced epoxy resin material for composite insulators based on the 3D‐Fick model

AbstractLong‐term exposure to moisture leads to a gradual deterioration of performance and reduced service life of glass fibre‐reinforced epoxy resin (GFRP) material in composite insulators. Therefore, it is necessary to analyse the moisture absorption characteristics of GFRP material and the evolution of damage to their internal interface properties. Moisture absorption tests on GFRP rod material used in composite insulators to obtain their three‐dimensional diffusion coefficients are conducted. Atomic force microscopy was then employed to obtain the composite material system's fibre/matrix interfacial phase parameters. Furthermore, a finite element model incorporating representative volume elements with interfacial phases and a mesoscale transient moisture absorption finite element model for the composite material was established. Finally, the moisture absorption characteristics of GFRP material and the evolution of damage to the interfacial phase under thermal‐humidity cycling conditions were investigated. The results showed that the diffusion coefficient along the fibre direction in GFRP material was higher than that in the perpendicular direction. The moisture diffusion finite element model, incorporating an anisotropic interfacial phase, fitted the anisotropic diffusion coefficients of GFRP material more accurately. As moisture invaded the GFRP material, the mismatch stresses continuously increased during the moisture absorption. Moreover, the non‐uniform arrangement of fibres resulted in uneven distribution of moisture‐induced stresses inside the material, leading to higher mismatch stresses in areas with dense fibre arrangements in the matrix. Prolonged high and low humidity cycles led to the development of micro‐cracks, micro‐porosity, and interface debonding along the fibre direction at the GFRP material interfaces, thereby affecting the anisotropic moisture absorption characteristics of the material. The findings of this study provide valuable insights into the mechanisms underlying the deterioration of GFRP material in composite insulator rods due to moisture degradation.

Analisis Umur Pakai Transformator Distribusi 800 Dan 1600 kVA Di PDAM Ngagel Surabaya

Distribution transformers have a very important role in the electric power system. The lifespan of transformers in electric power systems will decrease over time. The reduced service life of distribution transformers is caused by several factors, including loading, ambient temperature, transformer winding temperature and transformer oil temperature. The author uses quantitative and qualitative research types. This research was conducted to determine the remaining useful life of distribution transformers. The data used in this research are transformer template data and peak load data during the day and night. The results of data processing obtained state that the first transformer's estimated remaining life with a load > 80% is 18 years starting from 2023, the second transformer's estimated remaining life with a load > 80% is 16 years starting from 2023, for the third and fourth transformers it is not calculated because it has been used since 1982 or is around 41 years old. For the winding temperature on the first transformer LBP 84 ℃ and BP 89 ℃, on the second transformer the winding temperature LBP 81 ℃ and BP 96 ℃. Both transformers are still considered good because the hot spot temperature is below the maximum limit set by the IEEE in 1955, namely a temperature of 98 ℃.

A Review of Cavitation Erosion on Pumps and Valves in Nuclear Power Plants.

The cavitation erosion failure of pumps or valves induces the low efficiency and reduced service life of nuclear reactors. This paper reviews works regarding the cavitation erosion of pumps and valves in the nuclear power industry and academic research field. The cavitation erosion mechanisms of materials of pumps and valves are related to the microstructure and mechanical properties of the surface layer. The cavitation erosion resistance of austenitic stainless steel can be ten times higher than that of ferritic steel. The cavitation erosion of materials is related to the hardness, toughness, and martensitic transformation capacity. Erosion wear and erosion-corrosion research is also reviewed. Erosion wear is mainly influenced by the hardness of the material surface. Erosion-corrosion behavior is closely connected with the element composition. Measures for improving the cavitation erosion of pumps and valves are summarized in this paper. The cavitation erosion resistance of metallic materials can be enhanced by adding elements and coatings. Adhesion, inclusion content, and residual stress impact the cavitation erosion of materials with coatings.