Carbon Stainless Steel Research Articles

3D printed auxetic metal stiffener for lightweight metal–composite T-joints with high strength and toughness

A novel auxetic structure-based stiffener for stainless steel–carbon reinforced polymer (CFRP) T-joints with outstanding strength and toughness improvement is proposed. The stiffener was composed of a bulk web and re-entrant structure flange that was 3D printed using a selective laser melting 3D printer. The stiffener was bonded to a CFRP skin, and a pull-off test was performed to evaluate the pull-off strength, stiffness, and toughness of the joint. The results demonstrated that the proposed structure has specific strength and toughness that were 3.4 and 77 times greater than those of the baseline joint, respectively. The improvement in strength was due to the delayed damage initiation caused by the mismatch between the bending stiffness of the bulk web and the stiffener under the first re-entrant structure. However, the damage initiation in the baseline joint was located at the stiffener edge. Moreover, the negative Poisson's ratio of the re-entrant structure arrested the delamination growth after damage initiation, which enhances the toughness of the joint. By optimizing the structure of the stiffener, a joint with 2.66 and 38.2 times larger specific strengths and toughness compared to the baseline joint with the same specific stiffness was achieved.

Efficacy and power production performance of constructed wetlands coupled with microbial fuel cells for the advanced treatment of saline tailwater from wastewater treatment plants

In this study, the effects of different electrode materials and salt-tolerant plants on the efficacy and power production performance of constructed wetlands coupled microbial fuel cells (CW-MFCs) were analyzed for the advanced treatment of saline tailwater from wastewater treatment plants (WWTPs). The results showed that when carbon felt was used as the cathode material, the voltage was 165.45 ± 14.90 mV after system stabilization, the maximum power density was 3.20 mW/m2 when the current density was 25.58 mA/m2, and the power production performance of carbon felt was better than that of common titanium mesh and granular activated carbon-stainless steel mesh cathode materials (p < 0.05). When the two groups of systems were operated and stabilized, the average removal rates of TN, TP, NH4+-N and COD in RS-CW-MFC were 86.48 %, 88.1 %, 82.67 % and 88.96 %, respectively, and those of TN, TP, NH4+-N and COD in RN-CW-MFC were 84.33 %, 87.34 %, 81.63 % and 87.64 %, respectively. Salinity enhanced the power production efficiency by increasing ionic strength and decreasing the internal resistance of the system. The microbial community in the saline tailwater systems gradually evolved toward salt-tolerant species, which enhanced the power production efficiency of the system without affecting the treatment of traditional pollutants in the CW-MFC systems.

Mechanical behavior and property evaluations of electromagnetic shielding/far infrared functional composite boards made of nano carbon-stainless steel knitted fabrics and far infrared polypropylene

Mechanical behavior and property evaluations of electromagnetic shielding/far infrared functional composite boards made of nano carbon-stainless steel knitted fabrics and far infrared polypropylene

Interface Structure Change and Carbon Diffusion of Stainless Steel-Carbon Steel-Laminated Composite under High-Temperature Condition

Interface Structure Change and Carbon Diffusion of Stainless Steel-Carbon Steel-Laminated Composite under High-Temperature Condition

Corrosion Behaviors’ Investigation of Carbide Coatings Developed for Sulphuric Acid Recovery Systems

In this study, corrosion resistance of cobalt and nickel, which are known to have high corrosion resistance, reinforced tungsten carbide coatings applied to low carbon stainless steel material surfaces to reduce corrosion-induced losses in sulphuric acid recovery systems were investigated. During the recovery of sulphuric acid, aggressive sulphur systems in the baths cause the metal surface to dissolve and therefore a high amount of material loss occurs. In order to minimize corrosion induced material loss, 316 L stainless steel surfaces were coated with an interlayer of 95% nickel and 5% aluminium alloy, and then tungsten carbide coatings were synthesized on the surfaces of substrate materials reinforced with 13% cobalt and 13% nickel, respectively by thermal spraying method to further reduce the corrosion rate. Characterization of the produced coatings were carried out by X-ray diffraction (XRD), scanning electron microscope (SEM), optical microscope, image analyzer, and surface roughness device. The standard potentiodynamic polarization characteristics of the coatings for 1M H2SO4 solution at room temperature were investigated with a potentiostat/galvanostat device. As the obtained results, nickel reinforced tungsten carbide coatings with nickel aluminium interlayer showed the highest corrosion resistance against sulfuric acid environment with 0,41 mm/year corrosion rate. As a result of the article, the corrosion resistance of 316L stainless steels in sulfuric acid systems was improved by 5.02 and 3.15 times, respectively.

Evolution of microstructure, microhardness, crystallographic texture, and grain size variation in dissimilar joints used in concentrated solar power plants application

High carbon stainless steel 347H (SS347H) and Inconel 625 (IN625) are high-strength alloys, commonly used in high-temperature applications. These metals are commonly used in the fabrication of concentrated solar power energy storage tanks and pipelines. Construction of such tanks involves dissimilar welding as the primary manufacturing process. The critical factor to consider when joining two different materials is the development of microstructure, as it directly impacts the mechanical characteristics of the joints. According to the available literature, an increase in the heat input (HI) promotes alloying element segregation and susceptibility to weld cracking. Traditional arc welding processes, such as metal inert gas (MIG) welding, produce a higher HI. Therefore, there is a need to develop welding techniques that result in reduced HI. In the present study, a pulse-current MIG (PC-MIG) welding method was employed, utilizing current pulsing to minimize HI during the welding process. The welding was followed by metallographic and mechanical characterization. The microstructural examination found variations in microstructure at different regions. Electron backscatter diffraction analysis shows the crystallographic orientation at different regions. Analysis shows that both SS347H and IN625 have a face-centred cubic austenite structure. The inverse pole figure discloses strong texture formation. The average tensile strength of dissimilar weldments was found to be 479 MPa, while the average hardness value of the fusion zone was measured to be 235 HV. The research indicates that the PC-MIG technique is suitable for joining dissimilar materials with reduced HI, effectively eliminating the risk of cracking and enhancing the efficiency of the joint.

Numerical Investigation on the Electroslag Remelting of High Carbon Martensitic Stainless Steels

Control of solidification structure and segregation is crucial to improve the service performance of high carbon martensitic stainless steels. Design of the electroslag remelting (ESR) process based on the essential parameters of melting rate, filling ratio, and slag thickness is a precondition to achieve optimal control of solidification structure and segregation of the steels. However, there is still a lack of coupled works giving deep insight into the overall effect of the parameters on the expected control. With this background, a 2D numerical model was established to probe into the effect of process parameters. The results showed that: (1) With the increase of melting rate from 90 kg/h to 180 kg/h, the molten metal pool depth increased by about 4 cm. Meanwhile, the center LST, PDAS, and SDAS increased by about 450 s, 100 μm, and 12 μm. The segregation index of C and Cr increased by about 0.15 and 0.09. (2) As the filling ratio increased from 0.16 to 0.43, the depth of the metal pool decreased by about 4.5 cm, LST and SDAS received a slight increase of about 41 s and less than 5 μm, but PDAS had little change. The segregation index of C had an increase of about 0.03, but the segregation index of Cr demonstrated tiny changes. (3) As the slag thickness increased from 0.08 to 0.14 m, the metal pool depth presented a first increase of about 1 cm and then a slight decrease. The center LST, PDAS, and SDAS first increased by 148 s, 30 μm, and 4 μm and then decreased slightly. The changes of the segregation index of C and Cr presented a similar tendency than that of LST, but the changes are extremely small. (4) A low melting rate less than 120 kg/h, a filling ratio of about 0.23–0.33, and a slag thickness of 0.08–0.10 m were appropriate to obtain good performance for ESR of high carbon stainless steels in this study.

Unified viscoplasticity model for type 316 stainless steel subjected to isothermal and anisothermal-mechanical loading

316FR-type low carbon stainless steel is usually used for many advanced gas cooled reactor (AGR) power plants which are subjected to operating temperatures in the range of 500–650 °C under thermo-mechanical loading, which may lead to isothermal low cycle fatigue (LCF) and thermal mechanical fatigue (TMF) damage. The strain controlled thermo-mechanical fatigue test with and without holding time was carried out for 316FR-type stainless steel under the temperature cycling between 500 °C and 650 °C, and the strain ranges are Δε = ± 0.4%, ±0.8%, ±1.0% and ±1.2%, respectively. Within the framework of Abdel Karim and Ohno model, an improved unified viscoplastic constitutive model (UVM) is proposed to simulate the cyclic plastic behavior of 316FR stainless steel. The improved UVM includes strain rate sensitivity, temperature rate dependence, static recovery, average stress evolution and strain range dependence of cyclic hardening. And then based on the radial return mapping and backward Euler integration methods, the implicit stress integration algorithm and the new expressions of the consistent tangent modulus are derived respectively, the improved UVM is implemented by a User Material Subroutine into ABAQUS software again. The good correlation between simulation results and experimental data is obtained.

Extreme high-speed-rate laser directed energy deposition of high strength low carbon stainless steel coating with layered heterogeneous structure

In this work, a ferritic stainless steel coating was manufactured via extreme high-speed-rate directed energy deposition (EHLDED). Microstructural features and tensile behavior were investigated and analyzed. The microstructural analysis confirmed that EHLDED coating was characterized by alternating patterns of columnar dendrites and fine equiaxed dendrites. The average size of the dendrites was less than 1 μm. High-resolution transmission electron microscopy showed that there were a large number of dislocation lines (DLs) and dislocation tangles (DTs) enriched at inter-dendritic solidification structures attributed to the ultrahigh cooling and solidification as well as molten pool movement. In addition, a small percentage of predominantly nanosize carbides with the size ranging from 50 to 90 nm were also observed in dendrites and inter-dendritic solidification structures. The EHLDED coating sample manufactured at the deposition speed of 40 m/min showed a higher strength of 1084 MPa with the ductility 1.27%. Results reveal that the ultra-fine dendrites accompanied with nanosize carbides prepared by EHLDED contributed to achieving high strength of low carbon stainless steel coatings.

Mitigation of carbon steel biocorrosion using a green biocide enhanced by a nature-mimicking anti-biofilm peptide in a flow loop

Biocorrosion, also called microbiologically influenced corrosion (MIC), is a common operational threat to many industrial processes. It threatens carbon steel, stainless steel and many other metals. In the bioprocessing industry, reactor vessels in biomass processing and bioleaching are prone to MIC. MIC is caused by biofilms. The formation and morphology of biofilms can be impacted by fluid flow. Fluid velocity affects biocide distribution and MIC. Thus, assessing the efficacy of a biocide for the mitigation of MIC under flow condition is desired before a field trial. In this work, a benchtop closed flow loop bioreactor design was used to investigate the biocide mitigation of MIC of C1018 carbon steel at 25 °C for 7 days using enriched artificial seawater. An oilfield biofilm consortium was analyzed using metagenomics. The biofilm consortium was grown anaerobically in the flow loop which had a holding vessel for the culture medium and a chamber to hold C1018 carbon steel coupons. Peptide A (codename) was a chemically synthesized cyclic 14-mer (cys-ser-val-pro-tyr-asp-tyr-asn-trp-tyr-ser-asn-trp-cys) with its core 12-mer sequence originated from a biofilm dispersing protein secreted by a sea anemone which possesses a biofilm-free exterior. It was used as a biocide enhancer. The combination of 50 ppm (w/w) THPS (tetrakis hydroxymethyl phosphonium sulfate) biocide + 100 nM (180 ppb by mass) Peptide A resulted in extra 1-log reduction in the sulfate reducing bacteria (SRB) sessile cell count and the acid producing bacteria (APB) sessile cell count compared to 50 ppm THPS alone treatment. Furthermore, with the enhancement of 100 nM Peptide A, extra 44% reduction in weight loss and 36% abatement in corrosion pit depth were achieved compared to 50 ppm THPS alone treatment.Graphical

Non-cube-on-cube orientation relationship between M23C6 and austenite in an austenitic stainless steel

Crystallographic orientation relationship between M23C6 carbides and austenite in the lightweight high carbon stainless steel Fe−17Cr−9Ni−6Mn−4Al−0.42C (wt.%) was investigated by diffraction analysis in scanning and transmission electron microscopes. Electron backscatter diffraction analysis in SEM indicated the existence of an orientation relationship approximated by the Kurdjumov-Sachs (K-S) orientation relationship between the M23C6 carbides induced by aging and the austenitic matrix. The observation of an orientation relationship deviating from the commonly reported cube-on-cube orientation relationship was explained by the formation of M23C6 carbides via M7C3 carbides as an intermediate phase.

Desain dan Analisis Karakteristik Pegas Koil Sistem Suspensi Belakang untuk Kendaraan Ringan Sepeda Motor Listrik

The vehicle's suspension system have function to reduce vibrations from the shock between the wheels and the road. Previous research discussed the simulation of spring loading with material variations. This research focuses on the design and analysis of springs that will be used in Electric Motorbikes (SEMOLI). Spring analysis between cast stainless steels and carbon stainless steels is done by calculating displacement transmissibility. The analytical method used is the SDOF harmonic method to determine the system response. The results of the analysis are considered for the selection of springs by determining the displacement transmissibility and the response of the suspension system. The results of the analysis of the characteristics of cast stainless steels and carbon stainless steels for active springs 6, 7, and 8 at speeds of 10 km/hour, 20 km/hour, 40 km/hour, 80 km/hour showed a decrease in displacement transmissibility. Characteristics for stainless steel material at steady state condition with active spring 6 is 0.3 second, while 7 and 8 are 0.25 second. The characteristics of overshoot for cast stainless steel material with active spring 6 are 55.3%, 7 are 52.7% and 8 are 50.3%. Stainless steel material has the characteristics of overshoot on active spring 6 is 55.8%, active spring 7 is 53.3%, and active spring 8 is 51 From the characteristic analysis, the best material obtained is cast stainless steel with a smaller displacement value dan good respon.

ОСОБЕННОСТИ СТРУКТУРООБРАЗОВАНИЯ ПЕРЕХОДНОЙ ЗОНЫ В СЛОИСТОМ КОМПОЗИЦИОННОМ МАТЕРИАЛЕ, ПОЛУЧЕННОМ СВАРКОЙ ВЗРЫВОМ

The paper presents the research on special aspects of structure formation in the transition zones of a layer metal material made of structural carbon and alloy stainless steels with an internal protector. The authors specify the order of layers arrangement. As an industrial method of producing such a material, the explosion welding technology was selected, which ensures the production of three-, four- and six-layer materials with one and two internal protectors per one explosion. The selection of optimal process parameters was carried out using computer modeling in the LS-DYNA software product. By calculation, the authors determined the main technological parameters of the process, which provide in the contact zone at each interlayer boundary the ratio of the amplitude of the generated waves to their length in the range from 0.3 to 0.5. Mechanical tests of multilayer workpieces were carried out. The shear strength of layers was from 320 to 410 MPa, the ultimate tensile strength of the main layer was from 520 to 710 MPa, the impact resistance was from 290 to 740 kJ/m2, and the bending angle under static loading was 140 degrees and higher. The authors determined the phase composition and characteristics of the crystallographic structure of transition zones of a layer metal material with an internal protector. The study identified the presence of γ-Fe with a face-centered crystal lattice, two cubic structures, one hexagonal, and one orthorhombic. On the samples with artificial pitting, the authors determined their influence on the rate of anodic dissolution of a protective layer when contacting with an aggressive environment. The study shows that the interlayer boundaries with a homogeneous structure and minimal thickness have the highest corrosion resistance.

Effect of severe plastic deformation on aging kinetics of precipitation hardening 17–4 stainless steel

Precipitation hardening (PH) stainless steels are high chromium, high nickel and low carbon stainless steels which were mainly developed to provide high strength and fracture toughness while maintaining good corrosion resistance. Precipitation hardening treatment involves solution annealing treatment followed by aging treatment which is applied on these steel to impart high hardness, fracture toughness and strength. The PH stainless steels develop high strength and toughness through additions of copper, aluminum, titanium, niobium, vanadium, and/or nitrogen, which form precipitates during aging heat treatment. In this work effect of severe plastic deformation (SPD) on aging kinetics of pH 17–4 stainless steel was investigated. Severe plastic deformation was applied on the surface of pH stainless steel specimens by shot-peening process. For comparison, aging of specimens with shot-peening and without shot-peening were done. After aging specimens were characterized by microhardness testing, optical and electron microscopy. The results showed considerably high hardness in the range of 617–649 HV for pH 17–4 stainless steel after aging on severely deformed specimens which is nearly 29% higher than the specimens which were aged without SPD.

Extreme High-Speed-Rate Laser Directed Energy Deposition of High Strength Low Carbon Stainless Steel Coating with Layered Heterogeneous Structure

Extreme High-Speed-Rate Laser Directed Energy Deposition of High Strength Low Carbon Stainless Steel Coating with Layered Heterogeneous Structure

Extreme High-Speed-Rate Laser Directed Energy Deposition of High Strength Low Carbon Stainless Steel Coating with Layered Heterogeneous Structure

Extreme High-Speed-Rate Laser Directed Energy Deposition of High Strength Low Carbon Stainless Steel Coating with Layered Heterogeneous Structure

Finite Element Investigation on the Performance of Pressure Vessel Subjected to Structural Load

Pressure vessels are highly used in industries and in commercial purposes such as filtration, boiling, softening and hot water storage tanks. Pressure vessels are subjected to thermal loads and structural loads such as internal and external pressures which leads to its deformation. Present work focusses on the modeling of the pressure vessel according to standard dimensions using CREO 6.0 and analyzing it for three different materials and different pressure values using finite element approach. The materials considered in this study for the fabrication of pressure vessel are carbon steel, stainless steel, and titanium alloy. The finite element analysis results have been presented in graphical form. Results indicated that, titanium alloy is able to withstand high stresses and exhibited high factor of safety of 4.10. And among the steels, stainless steel demonstrated low structural performance.

Experimental Modeling of Pressure in the Hydrostatic Formation of a Cylindrical Cup with Different Materials

Forming complex sheet products using hydrostatic forming technology is currently a focus of the majority of forming processes. However, in order to increase stability during the forming process, it is necessary to identify and analyze the dependency of the forming pressure and the quality of a product on input parameters. For the purpose of modeling the forming pressure, this paper presents empirical research on the product of a cylindrical cup made of various materials, including carbon steel (DC04), copper (CDA260), and stainless steel (SUS 304) with different thicknesses (0.8 mm, 1.0 mm, and 1.2 mm), under a defined range of binder pressures. The regression method is selected to formulate an equation that shows the relationship between the input parameters, including the materials (ultimate strength and yield stress), workpiece thickness, binder pressure and the output parameter, and the formation of fluid pressure. The mathematical equation allows us to determine the extent of the effect of each input on the forming pressure. The experimental results can be used for the easier planning and forecasting of the process and product quality in hydrostatic forming.

316L Stainless Steel Microstructural, Mechanical, and Corrosion Behavior: A Comparison Between Spark Plasma Sintering, Laser Metal Deposition, and Cold Spray

Herein, Austenitic 316 low carbon stainless steel, a widely used grade for various applications, was studied to understand the effect of processing methods on the material properties. Steel samples were processed using spark plasma sintering (SPS), laser metal deposition (LMD), and cold spray (CS) techniques. Significant difference in hardness and yield strength was observed among the processed samples. The CS sample showed highest hardness (~ 378 Hv) and yield strength (~ 1390 MPa) compared to other samples. In addition to the desirable mechanical properties, corrosion resistance has a significant role in determining the service life of steel in corrosive environments. All the processed samples showed lower corrosion rate than the commercial steel. Results obtained from various characterization tools will be presented in-detail.

Simulation and Experimental Study on Three-roll Rolling of Stainless Steel-Carbon Steel Cladding Rebar

In this paper, ABAQUS is used to simulate the rolling process of stainless steel (304) and carbon steel (20MnSiV) clad steel bar by three rolls. Through analysis of different three-roll pass system, KNOCKS rolling mill system is selected as the finishing pass of rolling production line. Experimental results prove that finite element simulation result is right, it can be concluded that the thickness distribution of stainless steel-carbon steel cladding rebar rolled by KNOCKS rolling mill system cladding metal is more uniform, which can provide better finished products for the final pass rolling.