SUS304 Substrate Research Articles

Tribological behavior of detonation sprayed CrFeNiAl0.3Ti0.3 high entropy alloy coatings in seawater environment

In this study, the CrFeNiAl0.3Ti0.3 high entropy alloy coating was deposited onto a SUS304 substrate steel by detonation spraying. The CrFeNiAl0.3Ti0.3 coating consists of FCC, BCC and B2 phases. It’s hardness, bonding strength and porosity are 576 HV, 86 MPa and 0.87%, respectively. In seawater, the tribological properties of the coating depends on the counterparts. The CrFeNiAl0.3Ti0.3/SiC sliding-pairs presents the best tribological properties in seawater due to the lubricious SiO2·nH2O and a dense tribo-layer. For AISI 440 C and Al2O3 counterparts, moderate abrasive wear occurs for the coating. For CuZn40 alloy counterpart, a soft copper-rich tribo-layer reduces the wear. For Ti6Al4V counterpart, many hard TiO2 and Al2O3 abrasion particles lead to the severe wear of the two contacting surfaces.

A two-step laser-jet electrodeposition for the preparation of superhydrophobic surfaces on SUS304

A laser-jet electrodeposition step-by-step processing was used to fabricate a superhydrophobic surface with excellent performance on the SUS304 substrate. Firstly, different micro structures were obtained by laser texturing on the surface of the SUS304 substrate. Secondly, Ni-MoS2 composite coating was deposited on the SUS304 substrate with microstructure by jet electrodeposition. Previous research has shown that different sizes of microstructures can be processed on the substrate surface and exhibit different wettability if changing the scanning pitch of laser textures. Superhydrophobic surfaces with contact angles up to 156 ° and 151.5 ° were obtained when jet electrodeposited on the basis of laser scanning pitches with 1 and 1.5 times the laser spot diameter. Compared with hydrophobic surfaces only by the laser, the superhydrophobic surfaces have shown superior corrosion resistance and self-cleaning properties. In addition, the superhydrophobic surface produced by the two-step laser-jet electrodeposition still exhibits good superhydrophobicity after undergoing friction, which indicates that the superhydrophobic surface has excellent mechanical stability by two-step laser-jet electrodeposition.

Study on the performance of Lead zirconate titanate piezoelectric coating prepared by vacuum cold spraying

By utilizing the force-electric conversion capabilities of piezoelectric materials, piezoelectric ceramic coatings are intended to monitor the state of component damage. In this study, lead zirconate titanate [Pb(Zr, Ti)O3, PZT] piezoelectric ceramic coatings were prepared on the SUS304 substrate by vacuum cold spraying (VCS). The phase structure, microstructure, and electrical properties of the PZT coating were analyzed. According to the findings, the PZT coating has a typical tetragonal perovskite structure, and the Xi photoelectron spectrometer (XPS) findings show that the room-temperature deposition characteristics of VCS techniques do not affect the elemental valence state of PZT materials, making it a non-destructive way to create the coating. The surface of the PZT coating is uniform and smooth, and the surface roughness Ra is about 195 nm. The PZT coating has a microhardness of around 1,510 Hv and an elastic modulus of about 73.9 GPa. Meanwhile, the piezoelectric coefficient d33 of the PZT coating was about 46 pC/N. The maximum saturation polarization of the PZT coating was 16.2 μC/cm2, the remnant polarization was 3.1 μC/cm2, and the coercive field was 59.3 kV/cm, which showed some ferroelectricity. The dielectric constant/dielectric loss of the PZT coating was about 425/0.35. The Curie temperature of PZT coating is 392.6 °C, which improves the application temperature range of PZT coating. This demonstrates that the PZT coatings created by VCS have certain electrical capabilities, offering a novel way to create and enhance the piezoelectric ceramic coating system for later-stage part monitoring.

Fabrication of microtexture by pulse laser to improve the bonding strength of coating

ObjectiveIn order to improve the bonding strength between Zirconia (ZrO2) coating and SUS304 stainless steel through the machined surface texture. MethodsSUS304 stainless steel was processed by nanosecond pulse laser. Based on the analysis of the orthogonal test results and the summary of the law, the primary effects of different processing parameters on the processing size were judged according to the extreme difference. Nanosecond pulse laser was used to process the textures with different shape and coverage on the surface of materials. ZrO2 coatings were made by plasma spraying technology. ResultThe tensile test results show that square and triangular textures are easy to cause stress concentration, resulting in the decrease of coating adhesion. The stress concentration of circular texture is less, the adhesion between ZrO2 coating and SUS304 substrate is stronger. It is also found that the greater the texture coverage, the stronger the adhesion between ZrO2 coating and substrate, the coatings are less likely to fall off. The texture increases the contact area, so that the interlocking structures are formed between ZrO2 coating and SUS304.

Tribological study of Ti3SiC2/Cu5Si/TiC reinforced Co-based coatings on SUS304 steel by laser cladding

For the needs of the key moving parts of SUS304 steel in extreme environments, the composite coatings (Co-Ti 3 SiC 2 /Cu) were successfully fabricated by laser cladding. The tribological behaviors of three coatings at room temperature and 600 °C were systematically studied. Results indicated that the microhardness of the three coatings was 1.2–1.8 times higher than the SUS304 substrate. With the addition of the Ti 3 SiC 2 and Cu, the coating had good tribological capabilities, especially the anti-wear at room temperature was increased by 96%, and the friction reduction at 600 °C was increased by 73%, even it was found that Cu could promote the lubrication of Ti 3 SiC 2 . The wear of the three coatings changed from severe plastic deformation to slight oxidative adhesive wear . • The wear resistance of N3 coating was increased by 96% at 27 ℃, and the anti-friction was increased by 73% at 600 ℃. • The temperature cloud map could predict whether the material and the coatings formed an excellent metallurgical bonding. • At 600 °C, the Co-Ti 3 SiC 2 /Cu coatings formed the multi-layer of membrane-like sliding lubrication and oxide film wear. • The oxide film affected the overall lubrication effect and the Cu could enhance the lubrication of Ti 3 SiC 2 .

Fabrication of a Novel MgO-B2O3-SiO2-Zn Coating by Thermal Spraying

In automotive technology, the proper use of thermal insulation materials helps improve the performance and life of internal equipment and reduce maintenance cost. In this study, plasma spraying and flame spraying are used to prepare and coat a new MgO-B2O3-SiO2-Zn powder on the SUS304 substrate. The resulting coating as thermal insulation layer formed a networked microstructure between the substrates to improve the thermal insulation performance of the material. By validation of thermal radiation experiments, the thermal insulation effects of various ceramic powders were compared, the high-temperature and low-temperature thermal insulation materials for about 300 and 100 °C were determined, and the thermal insulation performance of the constructed material coatings was verified by analysis.

Contact cracking and delamination of thin solid lubricating films on deformable substrates

Effects of substrate plastic deformation on the cracking and delamination damage of thin solid lubricating films at sliding contacts were investigated. Diamond-like carbon films were evaluated by using micro-scratch tests. A three-dimensional finite element method was applied to analyze the stress-strain evolution of the film−substrate systems with consideration to the interfacial adhesion. Intense plastic deformations were generated in the softer SUS304 substrate due to the low shear strength, leading to parallel cracks along the track borders. A pile-up effect resulted in the film buckling and fragmentation ahead of the sliding stylus. However, on the harder M50 substrate, angular cracks in DLC films were generated at the trailing edge of the contact area, which led to wing-shaped spallation of the films.

Microstructures and Wear Resistance of Al<sub>1.5</sub>CrFeNiTi<sub>0.5 </sub>and Al<sub>1.5</sub>CrFeNiTi<sub>0.5</sub>W<sub>0.5</sub> High Entropy Alloy Coatings Manufactured by Laser Cladding

For the purpose of expanding the application scope of HEA coating manufactured on the surface modification of materials, in this work, the Al1.5CrFeNiTi0.5 and Al1.5CrFeNiTi0.5W0.5 HEA coatings were successfully manufactured using laser cladding method on SUS304. The microstructures and wear resistance of coatings are researched systematically. It is found that the W0 and W0.5 HEA coatings all exhibit the dendritic structure, which are constituted by BCC phases and Laves phases. With W element addition, the phase structures of W0.5 coating remain unchanged. W is dissolved in both two phases, but the solid solubility in Laves phase is higher compared to that in BCC phase. W0.5 coating with the highest microhardness of 848.34 HV, and the W0 coating with the microhardness of 811.45 HV, both of whose microhardness are four times more than that of SUS304 substrate. Among all samples, the W0.5 coating shows the optimal wear performance because of its larger content of hard second phase ( Laves phase).

Effect of Hydrothermal Treatment in Calcium Phosphate Solution on SUS304 Substrate

SUS 304 stainless steel is known to be a biocompatible material and is widely used as screws or plates. However, issues regarding iron ion release after implantation become a concern which limits the application of SUS304. Therefore, to overcome these shortcomings, surface modification on SUS304 by forming calcium layer is needed to disable iron release from the substrate and also to encourage cell attachment. In this study, initially SUS 304 substrate are subjected to electrolysis process in sodium chloride solution to form pitting corrosion. These pitting corrosion will give the anchoring effect for the calcium ions to attach. Then the substrate are subjected to hydrothermal treatment at 200°C in calcium phosphate solution for 24, 36, 48, and 60 hours for deposition of calcium ions on the pitted SUS304 surface. Surface morphology observed by scanning electron microscope (SEM) shows that the calcium ions were deposited on the surface of the SUS304 substrate regardless hydrothermal treatment time. Rockwell hardness values shows that as hydrothermal treatment time increased the hardness value decreases. Therefore, hydrothermal treatment method enables the deposition of calcium ions layer on the surface of SUS304 which will inhibit the release of iron ions and enhanced bone attachment with the implant due to the bonding of the calcium ions with the bone.

A material removal rate model-based chemical action of ultra-thin SUS304 substrate in chemical mechanical polishing

In this study, a mathematical model of material removal rate (MRR) is developed to investigate the chemical action during chemical mechanical polishing (CMP) of ultra-thin SUS304 substrate (thickness <0.1 mm) based on the theoretical analyses and the experiments. It is found that as the mass concentration of oxidants increases, the material removal rate of SUS304 substrate increases at first, then decreases. Additionally, the relationship between the MRR and the flow rate of the polishing slurry is observed. The MRR is proportional to the flow rate of acidic self-made polishing slurry. Furthermore, a better ultra-thin SUS304 substrate surface quality may be obtained after CMP when the mass concentration of H2O2 is 7.5 %. The present study also investigates the chemical and mechanical synergetic action mechanisms of the CMP process of SUS304 substrate.

Failure assessment of a hard brittle coating on a ductile substrate subjected to cyclic contact loading

Hard brittle films and coatings are often employed as a protective coating for metallic ductile substrates. In use, such coatings are generally subjected to cyclic/repeated contact loading and sliding over long periods of time. This study investigated the monotonic and cyclic contact fracture mechanism of hard coatings on ductile substrates (an electroplated Ni–P coating on a stainless steel substrate, SUS304) in order to evaluate their mechanical durability. In the experiment, both monotonic and cyclic indentation tests using a ball indenter with large contact force were performed. The fracture nucleation process was identified using the acoustic emission method. For monotonic contact loading (single indentation), coating cracks are produced by the excessive plastic deformation of the substrate, itself caused by contact loading, which makes the bending curvature of a coating a critical moment. Subsequently, cyclic contact loading (cyclic indentation) was applied to the coating in order to investigate the cycle number of film cracking. It was found that the critical contact force for coating fracture decreases, compared with that of monotonic loading. This critical force is dependent on the number of loading cycles. This may be due to the fact that cyclic contact loading encourages large plastic deformation of the SUS304 substrate owing to cyclic plasticity. Therefore, the cyclic plastic deformation behavior of the substrate was investigated using cyclic microindentation tests and the finite element method. In the computation, the Chaboche model was employed to compute the cyclic plastic deformation of the substrate, since it simulates cyclic plasticity. We clarified the cyclic contact fracture mechanism of electroplated Ni–P coating on an SUS304 substrate. Based on this, we finally predicted the coating lifetime (i.e., mechanical durability) under cyclic contact loading. Therefore, the present study is useful for obtaining information about film/coating fracture properties under both monotonic and cyclic contact loadings.

Effective Injection of Ceramics Nanoparticle Pastes into Plasma Spray for Speedy Layer Formation

Thermal nanoparticle spraying was developed to create fine ceramics layers on free surfaces. Resin slurry containing ceramics nanoparticles were atomized by a compressed air jet in a chamber, and the resulting micro mists of composited droplets were effectively injected from a tubular nozzle into the plasma flare. Alumina particles with average diameters of 200 nm were dispersed into the acrylic liquid resin at 40% volume ratio. The microsized mist droplets with average diameters of 20 μm were first formed using the compressed air jet under pressure of 2 atm, and then introduced into the arc plasma with an argon gas spray of 50 slpm in flow rate. The alumina layer of 300 μm thickness was formed successfully on the SUS-304 substrate of 50×50×5 mm in size, which was placed at a distance of 100 mm from the plasma gun, and a higher speed coating at the deposition rate of 50-100 μm/s was achieved. Crystal phases of the coated layer were analyzed by X-ray diffraction. The cross sectional microstructures were observed with optical and scanning electron microscopy. Porosities of the coated layers were estimated through dielectric constant measurements using terahertz wave spectroscopy.

22am2-E4 ステンレス板ばね構造を有するAlN圧電薄膜発電機

In this report, vibrational energy harvesters employing an aluminum nitride (AlN) thin film deposited on the stainless-steel (SUS304) was described. The piezoelectric AlN film was reactively sputtered on 50-μm-thick SUS304 substrate with AC magnetron system. The deposited film had a high c-orientation, and indicated FWHM of 1.34 deg for AlN(0002) peak. The developed energy harvesters with this film achieved the output power of 72.6 μW at 1 g acceleration when the vibration conditions were set to 65 Hz in frequency and 400 kΩ in load resistance.

J111014 酸化グラフェン分散水による摩擦減少効果 : 摺動材料による影響(〔J111〕摩擦・磨耗制御のための材料及び表面改質)

The problems of oil lubricants in waste and maintenance management are crucial for cost and environment. Water with less harmful to environment is suitable as a candidate lubricant to replace oil lubricants. However, water is lack of viscosity, which leads to high friction and severe wear between the sliding materials. Graphene Oxide (GO) is single layer graphite with oxygen functional groups and easy to be dispersed in water. In this study, the effect of friction reduction by water dispersed GO has been evaluated with different sliding materials. The friction coefficients between SUS304 substrate vs. SUS304 ball and SUS304 substrate vs. tungsten carbide (WC) ball were approximately 0.05. Severe wear was apparent on the SUS304 ball surface slid in the GO dispersion; however, only small wear was observed on the WC ball surface after friction test in the GO dispersion.

Design and fabrication of a double-sided piezoelectric transducer for harvesting vibration power

This investigation examines a means of integrating high-performance ZnO piezoelectric thin films with a flexible stainless steel substrate (SUS304) to fabricate a double-sided piezoelectric transducer for vibration-energy harvesting applications. The double-sided piezoelectric transducer is constructed by depositing ZnO piezoelectric thin films on both the front and the back sides of the SUS304 substrate. The titanium and platinum layers were deposited using a dual-gun DC sputtering system between the ZnO piezoelectric thin film and the back side of the SUS304 substrate. The scanning electron microscopy and X-ray diffraction of ZnO piezoelectric films reveal a rigid surface structure and a highly c-axis-preferring orientation. To fabricate a transducer with a low resonant frequency, a tip-mass of 0.5g and a vibration-area of 1cm2 are designed, based on the cantilever vibration theory. The maximum open circuit voltage of the power transducer is approximately 18V. After rectification and filtering through a 33nF capacitor, a specific power output of 1.31μW/cm2 is obtained from the transducers with a load resistance of 6MΩ. The variation of the power output of ±0.001% is obtained after 24-hour continuous test.

Designing a Piezoelectric Vibration-Energy Harvester Used for a Rapid IgE Allergy Sensing System Platform

This investigation examines a novel means of integrating high-performance AlN piezoelectric thin films with a flexible stainless steel substrate (SUS304) to fabricate a double-sided piezoelectric transducer for wind-power generators. The double-sided piezoelectric transducer is constructed by depositing AlN piezoelectric thin films on both the front and the back sides of SUS304 substrate. The titanium (Ti) and platinum (Pt) layers were deposited using a dual-gun DC sputtering system between the AlN piezoelectric thin film and the back side of the SUS304 substrate. Scanning electron microscopy and X-ray diffraction of AlN piezoelectric films reveal a rigid surface structure and highly c-axis-preferred orientation. To fabricate a transducer with a resonant frequency of about 90 Hz, a cantilever length of 1 cm and a vibration area of 1 cm2 are designed, based on the cantilever vibration theory. The maximum open circuit voltage of the power transducer is approximately 14.6 V.

Vibrational Characteristics and Young's Modulus of Stainless Steel Sheets Coated with some Inorganic Films

Young's modulus of coat films has been estimated by using the double-beam vibration-reed method. The 18-8 stainless steel (SUS304; JIS) sheets coated by some inorganic films were prepared by using the sputtering and CVD. The method are applied to estimate the modulus by using the fundamental mode resonant frequencies of coated substrate before and after deposition of the films. The resonant frequency of each sample was measured by shaking the sample, and the displacement response detected by the eddy current displacement sensor. The specimens include non-coated stainless, TiO2, CrN, TiN, and diamond-like carbon(DLC) coated sheets. The thickness of the coat films range from 0.4 to 3.5. The non-coated substrate specimen requires an adequate annealing corresponding to the thermal history of the film deposition. The measured resonant frequencies have some amplitude dependencies, therefore the frequencies were extrapolated to zero amplitude. The extrapolated frequencies, the modulus of the annealed substrate, density and the geometrical parameters were assigned to the formula of the resonant frequency for the double-beam. The measured modulus of SUS304 substrate, TiO2 and TiN films are smaller than bulk form. The measured modulus for the CrN film is larger than the one form the literature data. The modulus of DLC film falls onto the range of literatures.

Antireflection coatings with FeSi2 layer: Application to spectrally selective infrared emitter

We have developed efficient spectrally selective infrared (IR) emitters that can be utilized for thermophotovoltaic (TPV) power generation by using stainless steel (SUS304) substrates coated with β- FeSi2 thin films. To develop spectrally selective emitters, we theoretically propose antireflection (AR) coatings consisting of a single layer of a dielectric material having a high refractive index (∼5) and are appropriate for use with metals such as stainless steels in the IR region. This type of AR coating is fabricated by sputtering a β- FeSi2 thin film on a polished SUS304 substrate. The reflectance in the IR region is successfully reduced to less than 10%. In addition, the AR properties are stable even at 700 K in air. Therefore, metals with AR coatings of β- FeSi2 can be applied to IR emitters in TPV systems.

Abnormal spalling phenomena in the Sn-0.7Cu/Au/Ni/SUS304 interfacial reactions

The interfacial reactions in Sn-0.7wt%Cu/ENIG SUS304 couples at 240, 255, and 270 °C are examined in this study. The Ni-containing ternary Cu6Sn5 phase is formed at the Ni/liquid interface in the early reaction stage then it detaches massively from the SUS304 substrate and splits into two layers in the molten solder as the reaction time increases. This phase finally disintegrates and disappears. The square pillar-shaped FeSn2 phase is found on top of the SUS304 substrate when the Cu6Sn5 layer detaches. The reaction phase formation, detachment, and split mechanisms are proposed. The spalling phenomenon is reviewed and discussed. The growth mechanism of the FeSn2 phase obeys the parabolic law, and the activation energy is determined to be 112.5 KJ/mol.

Fabrication of micro-hole arrays using precision filled wax metal deposition

This study presents a low-cost hybrid fabrication process that produces micro-holes of less than 200 μm in diameter. First of all, a micro-EDM hole-drilling is employed to perforate micro-holes through the mirror-like substrate (SUS304), which is cylindrical in shape. The oily wax also known as “sacrificial material” is extruded and formed onto the SUS304 substrate, resulting in a precision cylindrical micro-wax pillar mould. A precision electroforming is then conducted to deposit a thick nickel metal layer onto the substrate, and subsequently the wax mould is completely removed and revealed a perforated micro-hole array after releasing from the substrate. Experimental results show that the wax mould has an excellent duplication capability. The finished micro-hole array has an average hole-diameter of 165.3 μm and demonstrates ideal geometric accuracy. The proposed approach can significantly cost down and contribute to the precision machining industry.