ПРИМЕНЕНИЕ ГИБРИДНОГО КОМПЛЕКСА «ОБЪЕМНАЯ ЭЛЕКТРОДУГОВАЯ НАПЛАВКА + ПОВЕРХНОСТНОЕ ЭЛЕКТРОДУГОВОЕ УПРОЧНЕНИЕ» ДЛЯ ПОВЫШЕНИЯ ХАРАКТЕРИСТИК АЛЮМИНИЕВОГО СПЛАВА АК5

. Production efficiency as well as the reduction of energy consumption and waste are the main drivers for the improvement of large-scale production in chemical industry. In addition, the demand for new processes – these days especially related to the chemical energy conversion as basis for the Energiewende – are additional triggers for innovation. Catalysis, well recognized by the public e.g. in form of the 3-way automobile catalyst, plays an important role for about 90% of all processes in chemical industry. The development of new and improved catalysts is a challenge for chemists – as is the search for new structural materials for mechanical engineers. Due to the often-necessary noble and thus expensive metals (e.g. palladium) in many catalysts, structural and chemical function have been developed separately in the two communities. Recent progress in catalytically active materials allows replacing expensive noble metals in selected catalytic processes by significant cheaper elements [1]. This offers the new perspective to combine structural and chemical functionality by innovative materials. Within this area, intermetallic compounds with their peculiar combination of crystal and electronic structure [2], represent an interesting class of materials to address this vision as will be shown in the contribution.

Micro arc oxidation (MAO), also known as plasma electrolytic oxidation (PEO), which is applied to obtain hard oxide coatings on aluminum alloys. The coatings formed during the MAO process are superior to anodic oxide coatings on plenty of properties, such as strong coating-substrate adhesion, adequate thickness, high hardness, excellent corrosion and wear resistance. There are several parameters affecting the properties of MAO coating, including composition of the substrate and electrolyte, process time, applied voltage and current density, but few works study the influence of cathodic current on MAO coating. This study investigated the effect of cathodic current density on the structures and properties of the coatings. The MAO coatings on 7075 Al alloys were obtained in aluminate-based electrolyte by using a bipolar pulsed power supply. The morphology, microstructure and compositions of the MAO coatings were characterized by using scanning electron microscope (SEM), X-ray diffraction (XRD), electron probe micro-analyzer (EPMA). The measurements of surface roughness, thickness, and microhardness were also conducted. Furthermore, the ball-on-disk tribometer and potentiodynamic polarization were used to evaluate the wear and corrosion resistance, respectively. Experimental results showed that the ceramic coatings are mainly composed of α-Al2O3 and γ-Al2O3. The microstructural observations of the MAO coatings revealed that with increasing cathodic current, the presence of pancake-like structure and the size of micro-pores are significantly reduced, meaning the coatings became smoother and more compact. Moreover, due to the low porosity and the phase composition, the microhardness of the ceramic coatings can reach ~1400 HV. With increasing cathodic current, the MAO coatings are nearly pore-free and crack-free. Therefore, the coatings exhibit an obvious improvement in corrosion and wear resistance.

Effect of critical plasma spray parameters on the microstructure, microhardness and wear and corrosion resistance of plasma sprayed alumina coatings

Effect of boronizing on microstructure, high-temperature wear and corrosion behavior of additive manufactured Inconel 718

Effect of shot peening and treatment temperature on wear and corrosion resistance of sequentially plasma treated AISI 316L steel

Lightweight high-strength Ti-based metal matrix composites (Ti-based MMCs) have a multitude of application applications, e.g., biomedical engineering, aerospace, and automotive, due to their good sustainability, high specific strength/stiffness, high elevated temperature strength, high wear, and corrosion resistance. Although there are metal matrix composite coatings comprised of polymers, composite, and ceramics materials, the paper primarily focuses on titanium-based composite coatings. This review also discusses the different coating techniques including electrodeposition, thermal spray, plasma spray, vapor deposition, and laser cladding to achieve high hardness and roughness, wear resistance and corrosion resistance. Totally, we attempt to bring out Ti based materials scenario for its current applications.

This study investigates the development of silver (Ag)-doped zirconia (ZrO2) coatings deposited on 316LVM stainless steel via the unbalanced magnetron sputtering technique. The oxygen content in the Ar/O2 gas mixture was systematically varied (12.5%, 25%, 37.5%, and 50%) to assess its influence on the resulting coating properties. In response to the growing demand for biomedical implants with improved durability and biocompatibility, the objective was to develop coatings that enhance both wear and corrosion resistance in physiological environments. The effects of silver incorporation and oxygen concentration on the structural, tribological, and electrochemical behavior of the coatings were systematically analyzed. X-ray diffraction (XRD) was employed to identify crystalline phases, while atomic force microscopy (AFM) was used to characterize surface topography prior to wear testing. Wear resistance was evaluated using a ball-on-plane tribometer under simulated prosthetic motion, applying a 5 N load with a bone pin as the counter body. Corrosion resistance was assessed through electrochemical impedance spectroscopy (EIS) in a physiological solution. Additionally, tribocorrosive performance was investigated by coupling tribological and electrochemical tests in Ringer’s lactate solution, simulating dynamic in vivo contact conditions. The results demonstrate that Ag doping, combined with increased oxygen content in the sputtering atmosphere, significantly improves both wear and corrosion resistance. Notably, the ZrO2-Ag coating deposited with 50% O2 exhibited the lowest wear volume (0.086 mm3) and a minimum coefficient of friction (0.0043) under a 5 N load. This same coating also displayed superior electrochemical performance, with the highest charge transfer resistance (38.83 kΩ·cm2) and the lowest corrosion current density (3.32 × 10−8 A/cm2). These findings confirm the high structural integrity and outstanding tribocorrosive behavior of the coating, highlighting its potential for application in biomedical implant technology.

In the present work, a low-carbon steel substrate was coated with Al2O3 and TiC using self-propagating high temperature synthesis. The synthesized coatings were annealed at 450 °C for 2–6 h. The characteristics of the substrate, coated, and annealed samples were examined, including microhardness, wear resistance, and corrosion resistance. A pin-on-disc tribometer was employed to conduct the wear test by varying the load, sliding velocity, and distance. The impact of these factors on the wear rate and worn surface morphology was then examined. Further, corrosion resistance was evaluated using electrochemical corrosion testing with 3.5 wt% NaCl as electrolyte. Results showed that Al2O3 and TiC specimens annealed at 450 °C for 5 h and 4 h improved the microhardness by 1.3 and 1.06 times than that of as-coated specimens respectively. The synthesized Al2O3 and TiC coatings showed an abrasive wear mechanism at higher loads and tribolayer formation was observed at higher sliding velocity and distances. The corrosion and wear resistances of the samples were found as follows: substrate< Al2O3 coated < TiC coated < Al2O3 annealed < TiC annealed. The Al2O3 and TiC ceramic coatings were found to improve wear and corrosion resistance having potential applications in cement, petrochemical, and marine industries.

Crucible CPM 420V is a unique tool steel made by the Crucible particle metallurgy (CPM) process. The alloy is designed from a martensitic stainless steel based analysis with added carbon and vanadium for exceptionally good wear resistance. CPM 420V offers significant improvements over CPM 440V in both wear and corrosion resistance. The exceptional wear resistance and good corrosion resistance of CPM 420V make it an excellent candidate to replace 440C and other corrosion- and wear-resistant materials, particularly where increased wear resistance is a primary concern. This datasheet provides information on composition, physical properties, hardness, and elasticity as well as fracture toughness. It also includes information on corrosion and wear resistance as well as heat treating and machining. Filing Code: SS-736. Producer or source: Crucible Service Centers.

Advancements in understanding the microstructure and properties of additive manufacturing Ti-6Al-4V alloy: A comprehensive review

Selecting suitable materials for automotive brake discs is an important process in the construction and assembly of braking systems. Brake discs or rotors are important components that convert kinetic energy into thermal energy to enable efficient braking and ensure vehicle and occupant safety. The choice of brake disc material is important to ensure optimum performance, reliability and durability under various operating conditions. Several important properties such as efficient heat dissipation, high mechanical strength, wear resistance and constant friction properties should be considered when choosing a suitable material for brake discs. Historically, Gray cast iron (GCI) continues to be the number one choice for brake discs due to its excellent heat transfer capabilities, effective vibration damping, and cost effectiveness. GCI effectively withstands the high temperatures and mechanical stresses encountered during braking, providing reliable and consistent performance. However, advances in materials science and engineering are researching alternative materials for brake disc applications Titanium alloys such as Ti-6Al-4V offer exceptional favour such as lightweight design, high-calibre strength, and corrosion resistance. These properties make titanium alloys suitable for certain applications that require reduced weight and increased performance. TMC combines a titanium matrix with ceramic reinforcements to improve performance compared to conventional materials. There are various factors to consider when choosing the brake disc material, such as: B. Vehicle type, weight, intended use (racing, daily driving, etc.), operating temperature, and cost considerations. Thorough testing and evaluation are performed to ensure that selected materials meet required performance criteria such as braking efficiency, durability, wear resistance and heat aging resistance. As the automotive industry continues to advance, there is more R&amp;D exploring advanced materials such as carbon-ceramic composites for high-performance and luxury vehicles. These materials provide excellent braking performance, weight savings and long life. Research Significance: The study of material selection for automotive brake discs will show results in the performance, reliability, and safety of braking systems. The aim is to identify suitable materials that improve braking efficiency, durability and thermal stability. Efforts in this area have led to improved braking performance through the development of materials with optimal friction properties. These materials result in shorter braking distances, increased responsiveness, and improved overall braking efficiency. Additionally, research is focused on identifying lightweight materials that maintain structural integrity and heat dissipation capabilities. This weight savings contributes to improved fuel efficiency, lower emissions, and improved vehicle handling and performance. Durability and longevity are important aspects studied in research. Materials with high mechanical strength and wear resistance are selected to ensure long-term durability and long service life. Effective heat dissipation is also an important factor. The aim of the research is to find materials with good thermal conductivity and stability. This prevents brake slippage and ensures smooth, reliable braking performance even under the most demanding conditions. Cost-effectiveness is also a consideration, as researchers strive to find materials that balance performance, durability, and cost. Identifying cost-effective materials without compromising safety and performance is critical for widespread adoption in the automotive industry. Methodology: Weighted Sum Method: It method is the mathematical approach by combines many factors or criteria by assigning weights to each of them. A weighted sum is calculated by the means of multiplying the weight of each one element by the corresponding value and summing it up. This method allows comprehensive evaluation and ranking of alternatives based on their weighted scores. It provides a simple and effective way to consider multiple factors at once and make decisions. Alternate Parameters: GRAY CAST IRON (GCI), TMC, AMC 1 &amp; AMC 2, TI-ALLOY (TI-6AL-4V). Evaluation Parameters: Friction coefficient tµ), Wear rate (x10^ {-6} mm^ {3}/N/m), Specific gravity (Mg/m^ {3}), Compressive Strength (MPa), Specific heat (Cp (KJ/Kg. K)). Result: From the result it is seen that Gray cast iron (GCI) got the first rank where as is the Ti-Alloy (Ti-6Al-4V) having the lowest rank. Conclusion: The first ranking material gray cast (GCI) is obtained with the best and suitable material for automotive brake disc.

Microstructure and wear-resistant behaviors of Al2O3-TiO2 reinforced Ni-based composite coating plasma-sprayed on 6061 aluminum alloy

Aluminum (Al) and its alloys are attractive for a variety of applications due to its advantages like light weight, ease of processing, and high thermal/electrical conductivities. However, it suffers short comings in terms of strength, wear resistance, and corrosion resistance. Thermal spray processes are widely used techniques for the surface property improvement like thermal, wear, and corrosion resistances of aluminum and other light metals. This paper summarizes the recent developments in thermal spraying and related technologies. Plasma spraying, flame spraying, and arc spraying are the chief thermal spraying techniques, whereas the HVOF and D-gun processes are the derivatives of flame spraying process. The cold spraying technique is an emerging coating technique where the particles are heated to a temperature lower than their melting point travel at high velocity and coat on impact with the target material by plastic deformation. Different parameters like heat source characteristics, coating material properties, substrate properties, and spray torch operating circumstances affect the coating microstructure and properties.

Deposition of NiCrBSi coatings by atmospheric plasma spraying and dry-ice blasting: Microstructure and wear resistance

Plasma electrolytic oxidation (PEO) is a very promising process that can enhance the corrosion and wear resistance by producing a relatively thick, dense and hard oxide ceramic coating on light alloys. The improvement in the corrosion behaviour of the treated metals strongly depends on some process parameters: current density, voltage, treatment time and electrolyte composition. In particular, the addition of additives in the electrolyte produces significant changes in the corrosion behaviour. The use of rare earth salts, especially of cerium and lanthanum, during PEO treatment was already studied in literature and the use of these salts improved the corrosion resistance of the obtained coatings. However, only few works reported the dissolution of rare earth salts in the electrolyte, whereas in the majority of studies these salts are used in pre‐treatment or post‐treatment solutions. In this work, the effect of the dissolution in the electrolyte of various concentrations of lanthanum nitrate on the corrosion properties of PEO coated 7075 aluminium alloy was studied. The base electrolyte was an alkaline solution containing sodium silicate and different concentrations of lanthanum nitrate (0.025, 0.05, 0.075 and 0.1 g/l). All the samples were treated with high current densities and for short treatment times. The morphology, thickness and composition of the protective layer were studied with SEM, energy‐dispersive X‐ray spectroscopy (EDS), X‐ray diffraction (XRD), glow‐discharge optical emission spectroscopy and X‐ray photoelectron spectroscopy (XPS). The corrosion resistance was evaluated performing potentiodynamic polarization tests and electrochemical impedance spectroscopy tests. PEO coatings obtained with additions between 0.05 and 0.075 g/l of lanthanum nitrate resulted more dense and adherent, as evidenced by SEM analysis. These additions of La(NO 3 ) 3 had a positive effect on the corrosion resistance causing the formation of a large passive zone. Copyright © 2016 John Wiley &amp; Sons, Ltd.