Steel Cladding Research Articles

Effect of slag recycling on bead geometry, dilution and microstructure in submerged arc cladding of stainless steels

The submerged arc welding (SAW) process generates a large quantity of slag, which, when disposed-of, harms the environment and wastes valuable ingredients. A technology was developed to recycle the SAW slag generated in stainless steel cladding, enabling its reuse as flux. Bead geometry and dilution play crucial roles in weld cladding. Dilution determines the minimum number of layers needed to achieve the desired chemistry, while bead width dictates the fewest passes required to cover the entire surface area. Additionally, bead geometry influences the mechanical strength of the clad layers. The microstructure and solidification mode also significantly affect clad quality. Therefore, understanding the impact of recycled slag on bead geometry, dilution, and microstructure is essential. This paper presents a systematic investigation into the effects of process variables and recycled slag on bead geometry and dilution in clad welding. It includes a comparison of microstructures obtained using fresh flux versus recycled slag. The results indicate that increasing the welding current (I) by 37.5% enhances weld penetration (p), bead width (w), reinforcement (r), and dilution (d) by 50.9%, 14.4%, 69.5%, and 5.5%, respectively. Conversely, increasing the travel speed (V) by 90%, decreases p, w, and r by 19.29%, 11.9%, and 25.3%, respectively; however, dilution (d) increases by 17.6%. On the other hand, increasing the open-circuit voltage (V) by 26.7% increases bead width (w) and dilution (d) by 10.4% and 5.4%, respectively, while reinforcement (r) decreases by 7.5%. Both single and multilayer claddings prepared with fresh flux and recycled slag exhibit similar microstructures.

Structure and Properties of Plasma Cladding of High-Speed Steel S2-9-2 (W2Mo9Al)

Structure and Properties of Plasma Cladding of High-Speed Steel S2-9-2 (W2Mo9Al)

Seismic Behavior of Concrete Beam-Column Joints Reinforced with Steel-Jacketed Grouting

Joints in frame structures often fail before beams and columns in an earthquake and are a key part of reinforcement. In this study, to enhance the seismic performance of concrete frame structures, a steel-jacketed grouting composite reinforcement method is proposed by combining reinforcement technology, steel cladding technology, and eco-efficient materials from grouting technology. This method effectively utilizes the advantages of various materials, avoids major demolition and construction, and reduces waste and resource consumption. In order to verify the feasibility and effectiveness of the reinforcement method, one of the original joint specimens with a scale of 1:3 and one of the reinforced joint specimens were designed and tested. The experiments involved reversed cyclic testing of beam–column to measure its seismic behavior. The seismic performance indexes such as failure characteristics, hysteretic properties, and the energy dissipation capacity of the specimens were analyzed, and the corresponding finite element model was established. The influence of key parameters such as reinforcement range, steel plate thickness, and grout strength on its seismic performance was explored. The research shows that the method can effectively improve the seismic performance of the joints, and seismic performance indexes such as bearing capacity, ductility, and energy consumption of the specimens are significantly improved. The test results of the established finite element model are in good agreement. The variable parameter analysis of the finite element shows that the thickness of the steel plate has little influence on its bearing capacity. With the increase in the reinforcement range of the clad steel and the strength of the grouting material, the bearing capacity of the specimen increases. The research results can provide a reference for the reinforcement of frame structure joints.

A Review on Metallurgical Issues in the Production and Welding Processes of Clad Steels.

Carbon and low-alloy steel plates clad with stainless steel or other metals are a good choice to meet the demand for cost-effective materials to be used in many corrosive environments. Numerous technical solutions are developed for the production of clad steel plates, as well as for their joining by fusion welding. For thick plates, a careful strategy is required in carrying out the multiple passes and in choosing the most suitable filler metals, having to take into account the composition of the base metal and the cladding layer. The specificity of the different processes and materials involved requires an adequate approach in the study of the metallurgical characteristics of clad steel, thus arousing the interest of researchers. Focusing mainly on ferritic steel plates clad with austenitic steel, this article aims to review the scientific literature of recent years which deals with both the production and the fusion welding processes. The metallurgical issues concerning the interfaces and the effects of microstructural characteristics on mechanical behaviour and corrosion resistance will be addressed; in particular, the effects on the fusion and thermally affected zones that form during the fusion welding and weld overlay processes will be analysed and discussed.

Mechanical and anti-icing performance of superhydrophobic aluminum conductor by anodized oxide technique

Abstract Anodized oxide technology is a traditional surface treatment method used in the material engineering field to enhance the friction, anti-icing, anti-corrosion, and insulation properties of Al-based samples. Considering the anti-icing and insulation performance, anodized oxide technology has great application prospects in overhead transmission lines. In this study, the preparation process of Aluminum (Al) flat plates and Aluminum Cable Steel-Reinforce (ACSR) was explored by using anodizing technology to obtain superhydrophobic properties. Moreover, as the significant performance in the application of transmission lines, the mechanical performance (tensile strength) of Al conductors was evaluated to study the impact of anodized oxidation technology. The results show that anodized oxide technology can improve the tensile strength of aluminum clad steel bars and aluminum-stranded wires in ACSRs. In addition, the hydrophobicity and anti-icing performance of anodized wires can demonstrate potential application prospects in the field of anti-icing.

Effect of oscillating laser cladding on microstructure and properties of stainless steel cladding layers

The laser cladding process is general accompanied by defects such as pores, cracks and uneven microstructure. In order to overcome the above defects, this study introduces the oscillating laser cladding technology, and uses oscillating laser cladding and without-oscillating laser cladding process to manufacturing the stainless steel cladding layers. The microstructure was characterized by XRD, SEM and EDS, and the microhardness, wear resistance and corrosion resistance of the cladding layer were analyzed by using vickers hardness tester, wear tester and electrochemical workstation. The results show that the oscillating laser cladding can have a great effect on the morphology and microstructure of the stainless cladding layer. Among the two cladding process, oscillating laser cladding can prepare a cladding layer with better properties. The grains in the oscillating laser cladding layer are obviously equiaxed, and the grain size is significantly smaller than that of without-oscillating laser cladding layers. In addition, the wear resistance and hardness of the oscillating laser cladding layer are higher than that of the without-oscillating laser cladding layer, but its corrosion resistance is slightly lower than that of the without-oscillating laser cladding layer.

Numerical modelling and design of cold-formed steel battens subject to pull-out failures under bushfire conditions

Thin and high strength cold-formed steel (CFS) battens and claddings serve as non-combustible elements in roof and wall cladding systems, aligning with the recommendations of Australian bushfire standards. However, they are susceptible to significant damage from heat and strong winds experienced during bushfire events, particularly in the form of batten pull-out failures. Such failures may occur at the screw connections between cladding and battens, or battens and trusses/rafters. However, pull-out failures often occur in the thinner CFS battens, when the screw fastener pulls out of the batten’s top flange, leading to the loss of entire cladding and compromising the integrity of the building envelope. This study used finite element modelling of a range of CFS batten configurations to investigate their pull-out failures under combined wind action and bushfire conditions. Finite element models were developed to simulate the pull-out failures at elevated temperatures, validated using experimental results and used in a parametric study to investigate the effects of relevant parameters. Using the results, this study has proposed suitable design equations for predicting the pull-out capacities of CFS battens at elevated temperatures. Engineers can use them to design bushfire safe CFS cladding systems.

A study on the performance of super duplex stainless steel cladding over mild steel using a CMT welding

Low carbon steels can be cladded with super-duplex stainless steels to enhance the surface’s mechanical and wear properties. The current study examines the impact of process parameters on weld bead geometry and dilution % during cold metal transfer (CMT) cladding of super duplex stainless steel 2507 over low carbon steel. Response Surface Methodology (RSM) with a Central Composite Design matrix was used to optimize the process parameters (welding current, welding speed, and nozzle to workpiece distance (NTD)). The adequacy of the model was checked using an ANOVA analysis. The optimal bead width, height, penetration, and dilution values were 8.05 mm, 4.52 mm, 1.56 mm and 14.64%, respectively. The ideal input parameters were 200 A of welding current, 4.64 mm/s of welding speed, and 14 mm of NTD. The welding speed is the most dominant parameter, followed by the welding current and NTD. The cladding samples were prepared from the optimal parameters. The CMT-clad layer’s microstructure, microhardness, and wear properties were also evaluated. The results indicate a dense crack-free and non-porous clad surface was obtained under optimal conditions.

Optimizing Hydride Stability in U-ZrHx Nuclear Fuel: The “Goldilocks Radius”

Nuclear-powered microreactors show great promise for opening new nuclear energy markets due to the flexibility offered by their rapid/streamlined in-factory fabrication, transportability, and self-regulating nature. The economic benefits of any commercialized nuclear reactor, however, rely on the system’s ability to produce large amounts of heat and efficiently convert that heat into electrical power reliably for long periods of time. Uranium-zirconium hydride (U-ZrHx) is currently being considered for compact reactor designs because it is a well-known nuclear fuel system that is self-moderating, but this fuel, which has historically been used for research reactors, has not been optimized for commercial power production. This paper analyzes the hydride stability of standard 304 stainless steel–clad U-ZrHx fuel under commercially relevant conditions. Fuel element design parameters, including physical dimensions, as-fabricated hydrogen content, burnup, peak fuel temperature, temperature gradient, operational fuel cycle duration, and volumetric heat generation rate, are discussed with a focus on hydrogen distribution and phase stability within the fuel element. Hydride stability declines more rapidly as the coolant temperature, burnup, and fuel cycle duration increase. Using a fuel-cladding gap material with heat transfer properties superior to air, such as helium or sodium, is essential to prolonging fuel hydride stability. The fuel’s physical dimensions are also important. At very small fuel diameters, the H/Zr ratio in the fuel meat decreases too rapidly due to the hydrogen content’s dependence on fuel meat volume. Conversely, the fuel meat temperature and temperature gradient exacerbate hydrogen loss at very large fuel diameters. We find that the most important parameter to consider when optimizing the hydride stability of U-ZrHx fuel is the relationship between the fuel meat radius and the power density in the fuel. A simple equation is empirically determined that relates the “Goldilocks radius,” that is, the fuel radius for which the H/Zr ratio is most stable, to the power density in the fuel.

Effect of Heat Treatments on the Microstructure and Mechanical Properties of SS317L/ASTM SA516 GR60 Steel Clad Plate Fabricated Through Hot Roll Bonding

Triple-layer stainless-steel clad plate having 317L stainless steel (SS317L) as cladding layer and ASTM SA516 GR60 (GR60) as backing layer was successfully fabricated through vacuum hot roll bonding (VHRB) at 1373 K (1100 °C) temperature and strain rate regime of 1–5 s−1, which were identified through process efficiency maps of the base materials (SS317L and GR60). The process efficiency maps were constructed by conducting isothermal compression tests within the temperature range of 1173 K (900 °C)–1473 K (1200 °C) and 0.1–50 s−1strain rate regime. Effect of post-rolling heat treatments on the mechanical properties of clad plate was studied after solutionization at 1173 K (900 °C) for 1 h followed by cooling at different rates, i.e., water quenching, air cooling, and furnace cooling. As compared to other post-rolling heat treatments, the ultimate tensile strength, uniform plastic elongation, and maximum shear strength showed a significant change from 524 MPa, 0.46 and 519 MPa to 652 MPa, 0.36 and 410 MPa, when the normalized clad plate was solutionized at 1173 K (900 °C) and water quenched. A drastic change in shear fracture mode from gradual failure in normalized condition to catastrophic failure was also noticed after water quenching. These changes are essentially manifestation of the microstructural change in GR60 layer which led to the change in mechanical properties.

Low-Cycle Fatigue Properties of Bimetallic Steel Bar with Buckling: Energy-Based Numerical and Experimental Investigations.

A bimetallic steel bar (BSB) consisting of stainless-steel cladding and carbon steel substrate exhibits excellent corrosion resistance and good mechanical properties. The bimetallic structure of BSBs may affect their low-cycle fatigue performance, and current investigations on the above issue are limited. In this study, the low-cycle fatigue properties of bimetallic steel bars (BSBs) with inelastic buckling were investigated. Experiments and numerical studies were conducted to investigate the low-cycle fatigue capacity for BSBs, considering buckling. The buckling mode of BSBs is discussed. The hysteretic loops and energy properties of BSBs with various slenderness ratios (L/D) and fatigue strain amplitudes (εa) are investigated. With increases in the L/D and εa, the original symmetry for hysteresis loops disappears gradually, which is caused by the buckling. A predictive equation revealing the relation between the εa and fatigue life is suggested, which considers the effects of the L/D. A numerical modelling method is suggested to predict the hysteretic curves of BSBs. The effect of buckling on the stress and energy properties of BSBs is discussed through the numerical analysis of 44 models including the effects of the L/D, εa, and cladding ratios. The numerical analysis results illustrate that the hysteresis loops of BSBs with various εa values exhibit similar shapes. The increase in the cladding ratio reduces the peak stress and the dissipated energy properties of BSBs. The hysteresis loop energy density decreases by about 3% with an increase of 0.1 in the cladding ratio. It is recommended that the proportion of stainless steel inBSBs should be minimized once the corrosion resistance requirements are met.

Investigation and evaluation of high-temperature lead-bismuth eutectic (LBE) corrosion resistance and compression performance of the FeCrAl-based coatings

The high-temperature lead-bismuth eutectic (LBE) corrosion resistance and ring compression performance of the Fe15Cr11Al2Si, Fe15Cr11Al0.5Y, and Fe15Cr11Al2Si0.5Y coatings were investigated. Even if the corrosion test temperature reaches 800 °C, all these coatings can effectively protect the steel cladding tube. After the corrosion test temperature exceeded 660 °C, an obvious Al-rich oxide layer was formed on the surface of the coating, and Al element enrichment occurred at the interface between the coating and the substrate. After the corrosion test at 800 °C, holes appeared in the thick interface layer of the Fe15Cr11Al2Si0.5Y coating. The Fe15Cr11Al2Si coating cracked after the ring compression test with a deformation rate of 3%, and the coating peeled off after the deformation rate reached 5%. When the deformation rate reached 5%, there was still no cracking in the Fe15Cr11Al0.5Y coating. When the deformation rate reached 30%, the coating cracked, but the cracked coating was still tightly bonded with the substrate. The Fe15Cr11Al2Si0.5Y coating has the worst compression performance, even if the deformation rate is 1%, the coating still peels off obviously. The underlying mechanism for the evolution of corrosion resistance and compression performance was discussed.

Research status and application of 304/Q235 stainless steel clad plate

Research status and application of 304/Q235 stainless steel clad plate

Understanding and Predicting the Thermodynamic Behavior of Fission Products Encountered Between the (U,Pu)O2 Fuel Pellet and the Cladding: Characterization and Modeling Approaches

This study provides a comprehensive investigation of the formation and behavior of a layer enriched in fission products encountered between the (U,Pu)O2 fuel pellet and the cladding, designated as JOG (“Joint Oxyde Gaine” in French). Employing a multifaceted approach that combined thermodynamic calculations, experimental synthesis, and advanced characterization techniques, simulated JOG has been synthetized (without radioactive fission products). Using thermodynamic calculations with the TAF-ID database, the phase compositions in the JOG was assessed for various temperatures, pressures, and oxygen potential conditions, revealing insights into the environmental factors influencing JOG formation. Experimental simulation of the JOG composition, exposed to controlled conditions, confirmed the presence of key compounds such as Cs2MoO4, CsI, and PdTe, as evidenced by SEM, EDS, and XRD analyses. The results of the calculations highlighted notable differences in the nature of the phases constituting the JOG under varying pressure and oxygen potential conditions. At 873 K and oxygen partial pressure of 10–4 bar, Cs2MoO4, Pd–Te, and a gas phase rich in tellurium and CsI were predominant, contrasting with the emergence of liquid phases at 70 bar. This study offered a comprehensive understanding of JOG microstructure, and highlighting the importance of accurate characterization for reactor safety. This information lays the foundations for future studies on the chemical interaction between the JOG and the steel cladding.

Effect of heat treatment on the microstructure, LBE corrosion resistance, and bonding strength of the FeCrAl‐based coatings

AbstractThe bonding strength and LBE corrosion resistance of the Fe15Cr11Al2Si, Fe15Cr11Al0.5Y, and Fe15Cr11Al2Si0.5Y coatings heat‐treated at 500–650°C for 500 h were investigated. The results showed that the as‐deposited Fe15Cr11Al0.5Y coating has the strongest bonding strength with the F/M steel cladding tube compared with the Fe15Cr11Al2Si and Fe15Cr11Al2Si0.5Y coatings. Heat treatment deteriorates the bonding performance of the coatings, and obvious enrichment of Cr and Al elements appeared. The consumed Al element inside the heat‐treated coatings promotes the formation of Fe3O4 on the surface of the coatings after the corrosion test. The Y element can inhibit the enrichment of elements and the formation of Fe3O4. The bonding strength of the heat‐treated coatings can be improved after the corrosion test. The underlying mechanism of the evolution of microstructure and properties of the coatings after heat treatment and corrosion test was discussed.

The Effect of Preheating and Current on the Development of Mild Steel Clad Layers via Stick Welding

The Effect of Preheating and Current on the Development of Mild Steel Clad Layers via Stick Welding

Failure Mechanisms in Stainless Steel/Carbon Steel Clad Plate Under Shear Tensile Loading: Experimental and Modeling Methods

The deformation behavior of a stainless steel/carbon steel (SS/CS) clad plate under interface shear loading is characterized in this work. A 2D digital image correlation method is applied to track the strain field variation near the interface during shear tensile tests. Then, a cohesive zone model (CZM) finite‐element method is developed to clarify the delamination behavior of the tested clad plate. Finally, the interfacial failure characteristics of the SS/CS clad plate are further presented through the comparison between the finite‐element method and fractography analysis at the interface. In the experimental and simulation results, it is shown that the mixed‐mode CZM, which couples the constitutive equations of three fracture modes, demonstrates excellent capabilities in capturing SS/CS interfacial deformation behavior. The main deformation mode in shear tensile tests is variable according to locations. The central region at the bonded surface is dominated by the shear delamination mode, and the region near the notches shows shifted crack propagation toward normal mode. These abrupt interfacial failures can be clarified via stress state and local damage analysis of the well‐reproduced finite‐element model of cladding material.

High bonding strength of Ti /steel clad plates prepared by a developed electromagnetic induction heating followed by rolling

Titanium/steel clad plates exhibit significant potential for industrial applications, such as petrochemical and aerospace, due to their combined advantages of two components. In the conventional hot rolling process, the formation of brittle intermetallic compounds (IMCs) had a detrimental effect on the mechanical properties of Ti/steel clad plates. Therefore, the present study proposed an electromagnetic induction heating rolling (EIHR) technique for efficiently fabricating Ti/steel clad plates with high bonding strength at a relatively low temperature, while avoiding the formation of brittle IMCs. Additionally, a pure iron DT4 interlayer with good fluidity was introduced between Ti and steel, which can further enhance both the interface bonding strength and elongation of the clad plates. Based on the electron backscattered diffraction characterization results of the interface, it was found that the addition a DT4 interlayer facilitated dynamic recrystallization of steel side and led to a reduction in dislocation density. Moreover, a pronounced {100}〈011〉 rotational cube texture was evident on the (100) pole figures as a result of substantial plastic deformation during the rolling process. Finally, the relationship between interface microstructure and mechanical performance was established.

PREPARATION OF COMPONENTS FOR ORBITAL WELDING OF TITANIUM TUBES WITH TITANIUM CLAD STEEL SIEVE BOTTOM

The article presents the method of preparing the tube sheet of a heat exchanger made of B265 Grade 1 titanium-clad steel with B338 grade 2 titanium tubes allowing for the qualification of the TIG (Tungsten Inert Gas) orbital welding technology. A test plate was made of A516M Grade 485 unalloyed steel clad with B265 Grade 1 titanium using the explosive method. The 300 x 300 mm plate consisted of a layer of 60 mm thick non alloy steel and 5 mm titanium clad. It had 20 holes drilled in a triangular arrangement, into tubes with a diameter of 34.93 mm made of B338 Grade 2 titanium with a thickness of 0.7 mm were welded. In order to obtain mechanical restraint inside the holes in the test plates, the titanium tubes were rolled out. For rolling, a five-roller was used, equipped with a retaining collar which allows the tube to move freely during rolling. The tests carried out showed that the proposed technology for preparing tube – sieve bottom elements allow for the preparation of a test plate for the qualification of welding technology. The test plate made in accordance with the technological assumptions met all the requirements necessary to qualify the technology for welding tubes with tube plates. Both in the case of non-destructive testing and macrographic testing, there were no problems with compliance with the PN-EN ISO 15614-8:2005 standard.

A new experimental methodology for investigating the impact of subsequent welding passes on the properties of the austenitic stainless clad steel plates welded joint: part I – a substrate case study

In this study, the influence of the applying repeated thermal cycling during welding on the microstructural transformations and mechanical properties in Austenitic Stainless Clad-Steel Plates (ASCSP) has been investigated, particularly in the substrate. For this purpose, a novel methodology was used, by filling the entire groove length and gradually shortening the subsequent passes. Afterwards, microstructural characterization of different zones in the welded joint was conducted using optical microscope. Results showed a decrease in acicular ferrite (AF) in the Weld Metal Substrate (WM-S) from the root pass (10 kJ/cm) to the second pass (13.5 kJ/cm). This decrease continued until a total disappearance by the third pass due to a heat input of 17.8 kJ/cm. Vickers micro-hardness test was used to investigate the effect of the subsequent passes on the mechanical properties of the joint. Micro-hardness examination confirms the metallurgical results. It was revealed that micro-hardness variations are influenced by AF percentage and pro-eutectoid ferrite levels.