Erosion Resistance Research Articles

Mechanical behavior and strengthening mechanism of loess stabilized with xanthan gum and guar gum biopolymers

Abstract The structural properties of loess are susceptible to change when subjected to external loads and complex environments, leading to various geological disasters. To investigate the mechanical behavior and strengthening mechanism of loess stabilized with biopolymers such as xanthan gum and guar gum, especially for soils with low bearing capacity and stability in engineering applications, we conducted research on the improvement of soil with xanthan gum and guar gum, tests including unconfined compressive strength, disintegration, direct shear, and microstructure tests were conducted. Among the four different dosages of biopolymers (0%, 0.5%, 1%, 2%) and four different curing ages (1 day, 3 days, 7 days, 14 days), the 2% content of biopolymer and 14 days had the greatest impact on the mechanical properties of loess, Both the compressive and shear strength, as well as the water stability of solidified loess, improve with higher content of xanthan gum and guar gum or prolonged curing time; however, the disintegration rate decreases. Microscopic analysis indicates that the biopolymers effectively fill the gaps between soil particles and attach to the particle surfaces, forming fibrous and reticular structures that improve the interparticle bonding and ultimately increase the strength and water stability of the loess. Xanthan gum and guar gum biopolymers can improve the mechanical properties and water stability of loess, enhance the erosion resistance and improve the water-holding capacity. These outcomes suggest that guar gum and xanthan gum biopolymers have the potential to serve as environmentally sustainable alternatives to conventional soil stabilizers.

Study on the development and dust suppression performance of a novel composite dust suppressant for metal mines

The significant amount of dust generated during the metal mining process affects both personnel health and the environment. Some mines, such as magnetite mines, produce magnetic dust that is easily adsorbed onto equipment, causing equipment failure and other issues. To solve such problems, a composite dust suppressant was synthesized in this study using carboxymethyl cellulose sodium (CMC-Na), primary alcohol ethoxylate (AEO), and polyethylene glycol (PEG) as raw materials. Firstly, the optimal ratio was determined according to the response surface method. Subsequently, the performance and dust reduction efficiency of the suppressant was evaluated. According to the optimal formulation ratio, the dust suppressant exhibited a viscosity of 34.5 mPa·s and a surface tension of 28.46 mN/m. The wind erosion resistance, compressive strength, and water retention of the dust samples were improved following the dust suppressant application. The loss rates were only 0.025% and 0.9% at wind speeds of 3.5 m/s and 20 m/s, respectively. Simulation experiments indicated that the suppressant achieved a dust suppression efficiency of 82.7% for respirable dust and 90.91% for total dust. These results demonstrate that the suppressant possesses high dust removal efficiency and effective dust suppression, aligning with the application requirements of metal mines and contributing to the mitigation of dust issues during mining operations.

Effect of Solid Particles in Polymer Waste Liquid on Grinding Tool Wall Erosion

Abstract With the continuous accumulation of polymer waste liquid in the third oil recovery process, the treatment of wellhead return waste liquid has become a key issue in oilfield exploitation and environmental protection. In this paper, the erosion failure of the cutter caused by sand-containing particles in the waste liquid during the shear grinding process is studied. The influence of the main structural parameters of the grinding tool and the erosion failure is studied by using the comprehensive numerical simulation method to reduce the erosion rate of the polymer flooding waste liquid on the cutter. Firstly, the flow field model of the solid-liquid fluid is established, and the erosion phenomenon on the tool wall is studied by combining the model with field experiments. In addition, the relationship between the different cutters structure and erosion rate of the grinding tool is studied, and the mathematical model is established. The optimized structural parameters are given to enhance the erosion resistance of the grinding tool in the process of polymer flooding wellhead waste liquid treatment and prolong its service life.

The impact of Microbially Induced Calcite Precipitation (MICP) on sand internal erosion resistance: A microfluidic study

Fine particle internal erosion involves the detachment, transport, and deposition of fine particles within soil, significantly impacting agriculture, engineering, and environmental protection. Microbially induced calcite precipitation (MICP) has proven to be an effective method for controlling internal erosion. To optimize MICP protocols for effective erosion control, understanding the microscopic mechanisms by which MICP reduces fine particle erosion is essential but remains unclear. In this study, microfluidic chip experiments were conducted to observe the characteristics of calcium carbonate crystals and fine particles before and after MICP reinforcement and erosion. Through quantitative analysis of the calcium carbonate produced by MICP and eroded fine particles, the effects of bacterial density, concentration of cementation solution, and flow rate on the efficiency of MICP in resisting soil internal erosion were investigated. In addition, three primary mechanisms by which MICP reduces fine particle erosion were identified. Firstly, in situ sand stabilization occurs when calcium carbonate generated by MICP bonds and encapsulates fine particles, forming larger particles that remain stable under erosive flow conditions. Secondly, regional sand stabilization is achieved as MICP-produced calcium carbonate crystals narrow or block the flow channels, preventing extensive migration of fine particles. Lastly, adjacent particle stabilization is facilitated by calcium carbonate crystals, which remain stable during water flow erosion and alter the erosion flow lines, creating zones adjacent to the crystals where fine particle movement is minimized. These findings provide a deeper understanding of the role of MICP in erosion control and can inform the development of more effective erosion mitigation strategies.

Superhydrophobic Yet Highly Thermally Conductive BN Composites for Electrical Erosion Resistance

Superhydrophobic Yet Highly Thermally Conductive BN Composites for Electrical Erosion Resistance

Enhancing wind turbine blade protection: Solid particle erosion resistant ceramic oxides-reinforced epoxy coatings

Wind energy has been regarded as one of the renewable energy sources to rely on in the future. In this aspect, wind turbine blade maintenance is quite a challenge in tropical areas like India. One of the main reasons why wind turbine blades get damaged and produce less energy is solid particle erosion. In the present work, nanocomposite epoxy (EP) coatings reinforced with Al2O3, ZrO2, and CeO2 nanoparticle fillers have been applied on glass fiber reinforced polymer (GFRP) substrates using a simple spray coating method. These nanoparticles have been prepared in-house by solution combustion synthesis (SCS) route using urea, glycine, and oxalyl dihydrazide fuels. X-ray diffraction, field emission scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy have been used to characterize the materials and coatings. EP coatings with different Al2O3, ZrO2, and CeO2 nanoparticle concentrations have been subjected to solid particle erosion resistance tests at impinging angles of 30°, 60° and 90°. ZrO2 and CeO2 nanoparticle-reinforced EP coatings show better resistance to solid particle erosion than Al2O3-reinforced coatings. Estimated average erosion rates are 17 and 11.3 × 10−3 mm3 g−1, respectively, for epoxy coatings with 20 and 40 wt% ZrO2 nanoparticles. However, GFRP substrate and neat EP coating show much higher erosion rates with respect to nanoparticles-reinforced EP coatings. To ascertain a correlation between H3/E2 and the solid particle erosion rates of the coatings, nanoindentation tests have been carried out. Tensile strength and initial modulus of all the coatings are found to be directly proportional to the average erosion rates, whereas, elongation at break shows an inverse relationship with the average erosion rate. This correlation of mechanical properties with solid particle erosion performance can play a critical role in the development of realistic simulation of protective coatings for wind turbine blades.

Coastal dune management affects above and belowground biotic characteristics.

Dune vegetation mediates dune-building through trapping wind-blown sand and reduces dune erosion by attenuating wave energy via above- and belowground biomass. Despite the role of vegetation in dune functions, the amount and distribution of biomass within a dune remains poorly quantified due to a lack of ample data. Our objectives were to determine the effects of management history and elevation on (1) dune belowground biotic structure and aboveground community composition and (2) to determine best predictors of belowground biomass. We sampled belowground biomass and sedimentology across the dune profile at sites in the Outer Banks, North Carolina, USA. Dunes were classified as either unmanaged (no anthropogenic interventions) or managed (sand fencing, vegetation planting, dune construction). Living belowground biomass was higher in unmanaged dunes and decreased with depth. Non-living belowground biomass was 50% higher than living biomass and with greater abundance in unmanaged dunes. Elevation was a significant covariate of living and non-living belowground biomass, vegetative cover and species richness. Plant community composition varied less in managed dunes and differed significantly from unmanaged dunes. Vegetative cover, species richness, elevation, sedimentology and management history were predictors of belowground biomass. These results underscore the influence of management and geomorphology on dune plant communities, which may influence erosion resistance.

Research on Sediment Erosion and Anti-Wear Coating Materials for Water-Intake Components of Hydraulic Turbines in Sandy Rivers

The operational efficiency, stability, and lifespan of hydroelectric power plants operating on sediment-laden rivers are affected by sediment erosion. A numerical simulation of the sand–water flow in the water-intake components of a turbine at a specific power station was conducted using the Euler–Lagrange method. Additionally, sediment erosion tests were carried out on the water-intake components coated with epoxy mortar material. The results indicate that sediment erosion on the stay vane surface mainly occurs on the front face, with the most severe erosion at the head, while sediment erosion on the stay ring surface primarily occurs near the stay vane head. The extent of erosion is mainly influenced by the distribution characteristics of sediment particles. The wear of epoxy mortar coating material is minimally affected by the spraying thickness. Adding 30% hardener to the epoxy mortar material can significantly improve the erosion resistance of the stay vane surface by about 30%. The erosion rate on the frontside of the stay vane is approximately 2.6 times that of the backside. Based on the sediment erosion tests and numerical simulation results of the sand–water flow, an estimation formula for the sediment erosion rate of the epoxy mortar erosion-resistant coating was established. This formula can be used to predict the anti-sediment erosion performance of epoxy mortar materials applied to the water-intake components of this turbine and similar river turbines.

Microstructure evolution and high-temperature erosion behaviors of laser cladded AlxCoCrFeNi2.1 HEA coatings

High entropy alloys (HEAs) are anticipated to be candidates for high-temperature applications. In this work, high-speed laser cladding has prepared AlxCoCrFeNi2.1 (1≤x≤1.4) HEA coatings with high Al content. The effects of Al content on the microstructure, microhardness, and high-temperature erosion behaviors have been systematically investigated. With the increase of Al content, the coating’s microstructure transforms from the dual-phase structure of FCC and BCC to a single-phase BCC structure. Correspondingly, the microhardness of HEA coating gradually increases at room temperature due to the increment of BCC proportion. The Al1.4 HEA coating, consisting of a single BCC phase, exhibits the highest resistance to solid-particle erosion at 600℃, while Al1.0 coating with FCC and BCC dual-phase structure takes the second place. Ploughing, fracture, and spalling occurred during the high-temperature erosion process of AlxCoCrFeNi2.1 HEA coatings. The synergistic interaction between the FCC and BCC phases in dual-phase coatings primarily influences erosion behaviors. However, oxidation resistance is critical to erosion resistance for single-phase BCC coatings.

Influence of Heat Treatment on Erosive Wear Resistance of High Cr Cast Irons

Influence of Heat Treatment on Erosive Wear Resistance of High Cr Cast Irons

CFD-DEM coupled study of erosion resistance characteristics of ribbed walls

Industrial bulk material transfer systems are exposed to high erosion risk due to prolonged scouring by particle flow. In order to improve the erosion resistance of the system components, this study proposes a wear-resistant improvement scheme by adding square and triangular ribs on the wall surface. A coupled CFD-DEM method was used to analyse the abrasion characteristics of particle flow hitting the flat and ribbed wall surfaces at different particle incidence angles, particle velocities and particle volume fractions. The results show that square ribbed plate is more targeted to reduce the erosion ratio of the groove surface and transfer the risk to the ribs, whereas triangular ribbed plate provides an optimal balance between sacrificial velocity and erosion resistance of the ribbed structure; moreover, square ribbed plate is slightly more capable of transferring the maximum wear to the ribs to reduce the risk of perforation of the wall surface. As the particle velocity increased from 5 m/s to 25 m/s, the triangular ribbed plate reduced the erosion ratio by up to 45 %; both square and triangular ribbed plate groove surfaces reduced the maximum wear rate by about 65 % and 35 %, respectively. With the increase of particle volume fraction from 0.025 % to 0.125 %, the erosion ratios of the square and triangular ribbed plates decreased rapidly by up to 16 % and 73 %, respectively; the groove surface of the square ribbed plate decreased by about 63 % of the maximum wear rate, while the groove surface of the triangular ribbed plate decreased by up to 48 % of the maximum wear rate.

Effect of atomic oxygen and vacuum thermal aging on graphene and glass fibre reinforced cyanate ester-based shape memory polymer composite for deployable thin wall structures

Deployable components and structures are a crucial part of space exploration. Due to fewer parts, low weight and cost, shape memory polymers (SMPs) and their composites (SMPCs) are considered ideal candidates for this. However, lower thermal stability and poor durability in the space environment have limited their applicability. This research work details the development of Graphene Nanoplatelets (GNP) filled Glass Fibre (GF) reinforced cyanate ester-based SMPC with 0/90° and ±45° sandwich fibre lay-up configuration capable of multidirectional shape programming. The SMP matrix was synthesised by mixing Cyanate Ester and Polyethylene Glycol (PEG) with added GNP. SMPC was fabricated by pouring the SMP mixture into a pre-prepared glass mould with the added GF layers. The synthesised SMPC showed shape programming and recovery at 169.01 ± 0.62 °C and stable thermomechanical properties at the temperature of 130 °C. Durability tests at extreme environmental conditions including Atomic Oxygen exposure, thermal vacuum aging, and elevated-temperature behaviour tests were conducted as these tests evaluate the durability and applicability of the SMPC for use in Earth's orbits and lunar environments. The performances of the samples before and after durability tests were measured through mechanical tests, shape memory effect tests and a series of characterisation methods such as microscopic image analysis, FTIR and dynamic mechanical analysis. According to the results, AO exposure affected the SMPCs by eroding their surface. There were no changes in the chemical structure of the SMPC yet the thermomechanical, mechanical and shape memory properties were decreased without compromising their safe operational levels such as storage onset temperatures (128.79 ± 3.08 °C), maximum tensile stress (114.99 ± 21.52 MPa), shape fixity (100 %) and recovery ratios (100 %). The erosion resistance of the GNP-filled SMPCs was improved with ∼54.35 % less erosion than the SMPC without GNP. The vacuum thermal aging slightly slowed shape recovery from 31.17 % to 8.32 % at 160 °C due to PEG crosslink degradation, however, 100 % shape recovery was achieved at the end. Further durability tests under cryogenic temperatures and effects after vacuum thermal cycles are warranted to observe the synergistic effect on the SMPC for future developments. Exploring the scalability and additive manufacturability of the developed SMPC can be advantageous in the future while mitigating challenges such as complex shape programming, long-term materials degradation, resource efficiency and compliance with safety standards.

Mechanical properties and micro-mechanism of seawater cementitious materials reinforced by in-situ polymerization

Understanding the potential mechanism of in-situ polymerization of acrylamide (AM) for modifying seawater cementitious materials is crucial for designing high-strength and durable marine concrete. Herein, the acrylamide (AM) in-situ polymerization was investigated for its effects on the hydration behavior, micro-morphology, and pore structure of cementitious materials mixed with seawater and freshwater through a series of elaborately designed microscopic characterization methods. The results reveal that the hydration process of cementitious materials proceeds simultaneously with in-situ polymerization. However, compared with freshwater mixtures, seawater provides a large number of metal ions and SO42- ions, which can cross-link with the generated polyacrylamide (PAM) during in-situ polymerization to form a three-dimensional network structure. The synergistic effect of the hydration, in-situ polymerization, and cross-linking processes of cementitious materials can improve the pore structure of seawater-mixed paste, enhance erosion resistance, and improve the stability and toughness of microstructure. These findings were further confirmed by comparing infrared spectroscopy results, hydration products, pore size, and micro-morphology analysis as well as flexural performance tests. This is of great significance to guide the design of novel materials in marine infrastructure.

Investigation into the cavitation erosion of rolled Ti6Al4V titanium alloy strengthened by the ultrasonic-assisted laser shock peening process

The novel process known as ultrasonic-assisted laser shock peening (ULSP) is conducted on hot rolled Ti6Al4V titanium alloy with polished surface to improve its cavitation erosion (CE) resistance. The microstructure and phase structure were investigated by transmission electron microscope and X-Ray diffractometer. The microhardness and residual stress were measured by microhardness tester and X-Ray residual stress analyzer. After that, the CE mass loss and morphology were analyzed through high-precision analytical balance and scanning electron microscope to reveal the CE resistance mechanism of ULSP. The results show that ULSP treatment causes plastic deformation at the surface layer, resulting in refined grains and complex dislocation structures. The aforementioned process produces a hardened layer and compressive residual stress (CRS) layer with notable amplitude and deep influence. The surface microhardness of the ULSP-9J specimen is 410 ± 4 HV, which is a 14.8 % increase compared to the LSP-9J specimen. The CRS of the ULSP-9J specimen is −329 ± 6 MPa. As a result, it is vital in preventing the formation and propagation of CE cracks, strengthening the material's resistance to CE damage, reducing mass loss, and enhancing the overall morphology of CE.

PS-PVD thermal barrier coatings microstructure modulation and high-temperature erosion resistance study

Plasma spray-physical vapor deposition (PS-PVD) enables the modulation of both the microstructure and the performance of the coating by modulating the ratio of the three phases (gas, liquid, and solid) present in the jet. Considering the observed deficiency in the erosion resistance of PS-PVD coatings, the study explores improving high-temperature erosion resistance in PS-PVD thermal barrier coatings by adjusting Ar/He flow ratios. At a plasma gas flow rate of 90 SLPM, increasing the Ar/He ratio enhances nanohardness and elastic modulus. An Ar/He ratio of 2:1 provides erosion resistance comparable to standard APS coatings. Raising the plasma flow to 120 SLPM with the same Ar/He ratio forms a dense coating with low erosion rates. The study identifies a strong correlation between the hardness of the coating and erosion resistance. Lateral cracking from high-temperature and high-speed particle erosion is identified as the primary cause of failure.

Planification of amorphous carbon coatings via periodically transitional sp2/sp3 bonds to enhance cavitation erosion resistance

In the marine sector, hydraulic machinery suffers severe damage from cavitation erosion. Although amorphous carbon (a-C) coatings are an effective measure to enhance the cavitation erosion resistance (CER), their widespread application is hindered by their metastable nature characterized by internal stress. In this study, a planification strategy was employed via different sp2/sp3 distributions (including uniform ones with different sp2/sp3 levels and periodically transitional ones with different periods), aiming to construct a pure a-C coating that enhances CER on 316L stainless steel by modulating the bias during magnetron sputtering. The effects of the sp2/sp3 distributions on the microstructure, chemical bonding, adhesion strength, fracture toughness, corrosion resistance and CER was investigated and compared with the coatings featuring uniform sp2/sp3 distributions. The results show that the periodic-mode coatings exhibit much higher CER due to their lower internal stress, excellent adhesion strength, enhanced fracture toughness and high corrosion resistance. After the cavitation erosion test for 4 h, the periodic-mode coatings only show striped structures without any coating delamination, along with less graphitization tendency during cavitation erosion. Hence, the design approach of periodic sp2/sp3 carbon bonds provides a promising new direction for marine equipment with improved CER and potential applications in various other environments.

Rare earth-doped ceramic coatings: Analysis of microstructure, mechanical properties, and slurry Erosion resistance using high pressure-high velocity oxy-liquid fuel deposition

The high pressure-high velocity oxy liquid fuel (HP-HVOLF) is a current industry-adopted thermal spraying technique for developing high melting point powder coating over surfaces. In the current manuscript, the rare earth (La2O3/CeO2/Er2O3–0.3 wt%. each) doped and without rare earth doped carbide (WC-10Co-4Cr) coatings have been deployed on stainless steel (SS410) via HP-HVOLF process. The comparison among the properties of the substrate, without rare earth coating and rare earth oxides doped coatings have been characterized by conducting mechanical, microstructural, and slurry jet erosion analysis. The results show that the hardness, modulus of elasticity, and flexural strength of the cermet coating are considerably higher for rare earth-doped coatings than those without rare earth-doped coatings and substrates (SS410). The EDX (energy dispersive X-ray spectroscopy) has recognized the occurrence of different elements on the surface together with rare earth. Moreover, its compounds such as Co3W3C and W2C were inveterate using X-ray diffraction (XRD) measurements. The porosity level of the rare earth doped, and un-doped coatings are obtained to be less than 1 % and≥1 to ≤2 % respectively. Moreover, the rare earth-doped cermet coated surface shows hydrophobic behavior with a maximum water contact angle (WCA) of ≈129.4°. Furthermore, the slurry jet behavior of rare earth doped coating shows high wear resistance as compared to without RE doped coatings, indicating its potential for robust performance under erosive conditions.

FEA-Guided development of Inconel 625 clad on mild steel using WAAM and their cavitation erosion resistance

FEA-Guided development of Inconel 625 clad on mild steel using WAAM and their cavitation erosion resistance

Structural design of two types of composites with high resistance to atomic oxygen attack based on polyimide matrices: a molecular dynamics simulation study

Because of their exceptional properties, polyimide (PI) polymers are widely used in various types of spacecraft. However, in low Earth orbit, spacecraft using these polymers are susceptible to atomic oxygen (AO) erosion, which will cause them to lose their original performance. Covering the PI surface with a protective coating and adding fillers to the PI matrix are two traditional methods to improve the AO erosion resistance of PI. However, a single protective method does not provide a good protective effect and does not necessarily balance the relationship between the AO resistance of the composites and other properties, such as mechanical properties. The structural design of composites can perfectly solve such problems. Therefore, two kinds of AO-resistant materials based on the PI matrix are designed in this paper, one is a hybrid-filled composite with nano-silica filler and graphene filler, and the other is a double-layer coated composite based on the structural design of a traditional bulletproof vest. And the AO incidence simulation of these two types of materials was carried out using ReaxFF-based MD simulation. The results show that the mixed filling of graphene and nano-silica not only greatly improves the AO resistance of the PI matrix, but also greatly improves the tensile mechanical properties of the matrix by adjusting the appropriate mixing ratio. The structure of PI-Gr-SiO2 (The structures are PI, Gr and SiO2 from bottom up, respectively. SiO2 will be the first to take the impact of AO.) possesses excellent resistance to AO erosion, and at the end of 64 ps of AO erosion, the PI matrix did not suffer any damage. This paper provides a new idea of material structure design using the MD method, which provides a new approach to improve the AO erosion resistance of PI and is expected to design new composites adapted to a variety of extreme environments in the future.

Assessment of the microstructure, adhesion and elevated temperature erosion resistance of plasma-sprayed NiCrAlY/cr3C2/h-bn composite coating

This study uses an air jet erosion tester to investigate the erosion behavior of NiCrAlY/Cr3C2/h-BN composite coatings that are plasma-sprayed at three different temperatures and 40 m/s on T22 boiler steel alloy. 30 and 90° are the impingement angles. To identify the erosion mechanism, SEM and X-ray diffraction techniques are used to analyze the surface morphology and phase generated on the eroded surface. Findings of erosion test indicate that the erosion resistance was notably enhanced by addition of Cr3C2 and h-BN because of its lubricating characteristics and capacity to reduce frictional forces during erosion. The combined influence of Cr3C2 and h-BN enhanced the coating hardness and erosion wear resistance, thereby improving its overall resistance to erosion. The weight loss method was employed to calculate the erosion rate, and the NiCrAlY/Cr3C2/h-BN coating showed up to 30.55% and 34.48% lower erosion rate as compared to uncoated T22 substrate at 600 °C for 30° and 90° impact angles, respectively. This characteristic is affected by the hard reinforcement Cr3C2's high-temperature stability, the h-BN's self-lubricating ability, the formation of a protective oxide layer that forms at 600 °C, and the eroded coating's ductile behavior of material removal. The study also reveals that the NiCrAlY/Cr3C2/h-BN coating system on T22 boiler steel alloy has excellent erosion resistance, making it suitable for use in high-temperature and erosive environments in boiler systems and similar industries.