Explosive Cladding Research Articles

Zastosowanie technologii wybuchowego platerowania metali do wytwarzania nowych zaawansowanych materiałów warstwowych na przykładzie połączenia tytan Ti6Al4 – aluminium AA2519

Explosive metal cladding technology has been extensively developed since the mid-20th century. It is an area with the largest use of explosives for civil purposes, apart from mining. The global production of these materials runs at tens of thousands of square metres annually. Explosive bonding enables the production of a wide range of intermetallic compositions where, in many cases, no alternative methods are available. As an example, layered products include clad plates made of light metals, e.g. titanium, aluminium, magnesium showing different melting points, densities and hardness. Each new material combination requires an adaptation of the technology used by selecting suitable bonding parameters and new modified explosives. Several variants of Ti6Al4V/AA2519 explosive alloy bonding technology were created. The clad plates were tested using destructive and non-destructive techniques to determine bond strength and integrity. The study aimed to create new materials with improved ballistic resistance for structures used in the aviation and space industry.

Characterization of the Microstructure and Bonding Properties of Zirconium-Carbon Steel Clad Materials by Explosive Welding.

An investigation was carried out to characterize the microstructure and bonding properties of the zirconium-carbon steel explosive clad. The microstructure and the composition of the clad were characterized using optical microscopy and scanning electron microscopy. Bonding properties were inspected by using bending and shearing tests. The examination results indicate that the R60702 and Cr70 plates were joined successfully without visible defects. The interface wave is symmetrical. There is no element diffusion across the interface of the clad plate. There are melt blocks at the interface. Bending and shearing test results indicate that the bonding properties of the clad meet the requirements of the ASTM B898 specification. And after shell rolling, no delamination appeared at the interface. Thus, it indicates that the clad plates have good bonding quality and meet the processing requirement.

Numerical and experimental investigation on aluminum 6061-V-grooved stainless steel 304 explosive cladding

This study attempts to analyze the microstructure and interface behavior of aluminum 6061 (Al 6061)-V-grooved stainless steel (SS304) explosive cladding by numerical and experimental methods. Numerical simulation was performed by Smoothed Particle Hydrodynamics (SPH) technique, in ANSYS AUTODYN, and the results are correlated with experimental outcome. The machining of V-grooves on the base plate transform the melted layer formed in conventional cladding (without grooves on the base plate) into a smooth undulating interface, for a similar experimental condition. The flyer plate and collision velocities, observed in numerical simulation, are in good agreement to the analytical expectations. The pressure developed in the flyer plate is higher than the base plate and the maximum pressure is witnessed at the collision point irrespective of grooved base plate or otherwise. The temperature developed in the collision point of conventional explosive cladding exceeds the melting point of both the participant metals, whereas, it exceeds the melting point of aluminum alone, in case of V-grooved base plate cladding. The shear and impact strengths of the V-grooved base plate clads are higher than the conventional clads and the fracture surfaces exhibit mixed modes of fracture.

Microstructure and Mechanical Strength Predictive Modeling in Al 5052-Trapezoidal Grooved SS 304 Explosive Cladding

Aluminum alloy plates were explosively cladded to stainless steel plates with trapezoidal grooves on the mating surface. The process parameters viz, loading ratio, standoff distance and flyer plate thickness were varied based on the Taguchi analogy. The variation in the process parameters alters the kinetic energy dissipation and the deformation work performed at the interface, and dictates the interfacial wave amplitude and the mechanical strength of the dissimilar explosive clad. The optimum level of process parameters for attaining higher tensile and shear strength is computed by signal-to-noise ratio. Further, a mathematical model is developed for calculating tensile and shear strength of the clad, based on the regression analysis using statistical software Minitab-16, and the level of fit is determined by analysis of variance.

Studies on wire-mesh and silicon carbide particle reinforcements in explosive cladding of Al 1100-Al 5052 sheets

Abstract This study focuses on the development of stainless steel wire-mesh (WM) and silicon carbide particle (SiCp) reinforced hybrid aluminum composites with improved microstructural, corrosion and mechanical properties. Aluminum 5052-Aluminum 1100 sheets were explosively cladded with different reinforcements viz., stainless steel SS316 wire-mesh and silicon carbide powder (1.5 % and 3 % by weight of flyer plate) to produce composites at varied loading ratios, LR (Mass of explosive/mass of flyer plate=0.6 to 0.9), and the results are reported. Microstructural characterization of the conventional and wire-mesh reinforced clads display a slender melted layer, which transformed into a smooth interface when SiC particles are added as reinforcement. Maximum hardness is witnessed at the interface for the attempted conditions irrespective of the reinforcement employed. The explosive clad reinforced with wire-mesh and 1.5 % SiCp particles exhibit higher tensile and shear strength. The corrosion rate of the clad is higher in the initial days and tends to follow a uniform fashion afterwards.

Experimental and numerical studies on aluminum-stainless steel explosive cladding

In this study, the effect of varied loading ratio (mass of the explosive/mass of flyer plate) on the nature of interface, temperature and pressure developed in aluminum-steel explosive cladding is presented. Increase in the loading ratio, R, enhances the pressure developed, kinetic energy utilization and deformation work performed. Interfacial microstructures exhibit the formation of molten layer at few spots, owing to the increase in temperature beyond the melting point of parent alloy. The increase in temperature and the quantum of pressure developed were determined by numerical simulation performed in Ansys AUTODYN by employing smoothed particle hydrodynamics (SPH) method. The positioning of the experimental conditions on the weldability window is presented as well.

Process Parameter Optimization to Achieve Higher Impact Strength in SS316 Wire-Mesh and SiCp Reinforced Aluminum Composite Laminates Produced by Explosive Cladding

In this research paper, an empirical relationship is developed to envisage the impact strength of stainless steel wire-mesh and SiCp reinforced aluminum composite laminates produced through the explosive cladding. The process parameters viz., stand-off distance, explosive loading ratio, wire-mesh orientation and wt% of SiCp were optimized in four factors, three levels Box–Behnken design with full appropriateness. Analysis of Variance indicates that the wt% of SiCp possess the greatest sway on impact strength, trailed by stand-off distance, explosive loading ratio and wire-mesh orientation. The interfacial microstructure of the optimized condition reveals the presence of silicon carbide (SiC) as the wt% of SiCp is increased from 0 to 3%. X-ray diffraction analysis of the clad interface shows the absence of brittle intermetallic compounds. The impact fracture faces of the optimized clad reveals a ductile manner of fracture with elevated impact strength.

Study on microstructure and properties of TA1-304 stainless steel explosive welding cladding plate

Bonding TA1 and 304 stainless steel by explosive welding to obtain cladding plate. the microstructure of the bonded interface of the cladding plate was analyzed and its properties were tested. It was observed that the bonding interface of the cladding plate was periodically wavy. There is a large melting zone at the end of the interface waveform, and a vortex exists near the melting zone. The EDS surface scanning of the interface shows that there is element diffusion at the interface, and it is speculated that the bonding at the interface of the cladding plate belongs to metallurgical bonding. The microhardness measurement results show that the Vickers hardness (HV) at the interface is up to 413.10, and then the microhardness is lower with the distance from the interface junction, and gradually decreases to the same raw material. The tensile strength of 304 material after explosive welding reached 865MPa; the longitudinal shear strength of titanium-stainless steel cladding plate was 325MPa, and the transverse shear strength was 309MPa; The tested cladding plate has excellent corrosion resistance, and its corrosion resistance is between TA1 and 304. The self-corrosion current of the cladding plate is 233 μA.

Effect of silicon carbide and wire-mesh reinforcements in dissimilar grade aluminium explosive clad composites

Aluminium composites are inevitable in the manufacture of aircraft structural elements owing to less weight, superior corrosion resistance and higher specific properties. These composites reduce the weight of the aircraft, improve the fuel efficiency and enhance the maintenance duration. This study proposes the development of dissimilar grade aluminium (aluminium 1100-aluminium 5052) composites with different reinforcement’s viz., stainless steel wire-mesh, silicon carbide (SiC) powders and SiC powder interspersed wire-mesh, by explosive cladding technique. Wire-mesh enhances the friction and restricts the movement of flyer plate to craft a defect free clad, while SiC particles form a band on the interface. Highest strength is obtained when SiC powder interspersed wire mesh is employed as reinforcement. The dissimilar aluminium explosive clad with SiC particle reinforcement results in lower strength, which is higher than that of the weaker parent alloy and that of the conventional dissimilar aluminium explosive clads without any reinforcement.

TEM Characterization of Explosive Cladding Interfaces between Refractory Metal (group V or VI) and Cu Plates

TEM Characterization of Explosive Cladding Interfaces between Refractory Metal (group V or VI) and Cu Plates

Microstructural characterization of silicon carbide reinforced dissimilar grade aluminium explosive clads

Aluminium composites are inevitable in ship building, commercial and defence aircrafts construction due to their light weight, high strength to weight ratio, admirable properties and cost affordability. In this study, the microstructural characteristics of explosive cladded dissimilar grade aluminium (Al 1100-A1 5052) clad composites reinforced with silicon carbide (SiC) particles is presented. Microstructure taken at the interface by optical and scanning electron microscopes (SEM) revealed the formation of a silicon carbide layer between the dissimilar grade aluminium sheets. Though reaction layers were witnessed at few locations along the interface, the diffusion of atoms between the participant metals is not visible as confirmed by energy dispersive spectroscopy, elemental mapping, line analysis and X-ray diffraction (XRD). The variation in microhardness at various regions of the silicon carbide reinforced dissimilar aluminium explosive clad is reported. The increase in tensile strength of the SiC laced clad is also presented.

Effect of silicon carbide particles in microstructure and mechanical properties of dissimilar aluminium explosive cladding

Explosive cladding of aluminium 1100 and aluminium 5052 sheets, with silicon carbide (SiC) particles dispersed between them, was attempted. The quantity of SiC particles was varied from 6 to 12%, by weight (0.1–0.2 mm thickness), of the flyer plate. The introduction of SiC particles between the dissimilar aluminium sheets transformed the molten layer formed at the interface in conventional cladding (Al 1100-Al 5052) to a silicon carbide layer devoid of defects. The thickness of SiC layer varied from a slender to thick agglomeration with the quantity of SiC particle added. In addition, the effect of SiC particles on the mechanical strength of the dissimilar aluminium explosive clad is discussed. It is observed that the explosive clad containing 10% of SiC particles exhibited a better microstructure and results in higher mechanical strength as well.

A finite element based state-space approach for vibration analysis of slender explosive clad pipe with partial contact defect

Abstract An efficient modeling method is presented in this paper for vibration analysis of explosive clad pipe with partial contact defect (PCD). The principal purpose is to study the effects of the PCD on the vibration characteristics of explosive clad pipe and to explore effective techniques for detecting the PCD. The slender explosive clad pipe is regarded as two parallel elastic beams continuously joined by a virtual Winkler/Pasternak type viscoelastic layer, and the virtual layer is capable to describe the non-uniform bonding state such as the PCD. By means of finite element method and the standard linear solid (SLS) model, a state-space model of explosive clad pipe with inhomogeneous bonding state is developed for the fields of axial displacement and transverse displacement. The model can reflect the PCD pipe system under different boundary conditions and describe damping behavior of bonding interface. Experiments and numerical examples available in the literature demonstrate the accuracy and reliability of proposed approach. Finally, numerical results are presented and show that the PCD have significant effect on the natural frequencies and forced response in high-frequency domain. A potential method for identifying the length and position of the PCD in explosive clad pipe is also discussed in this paper.

EXPLOSIVE CLADDING OF ALUMINIUM 5052-STAINLESS STEEL 304

This study addresses the effect of process parameters viz., loading ratio (mass of explosive/mass of flyer plate) and preset angle on dynamic bend angle, collision velocity and flyer plate velocity in dissimilar explosive cladding. In addition, the variation in interfacial microstructure and mechanical strength of aluminium 5052-stainless steel 304 explosive clads is reported. The interface exhibits a characteristic undulating interface with a continuous molten layer formation. The interfacial amplitude increases with the loading ratio and preset angle. Maximum hardness is observed at regions closer to the interface

Influence of Grooved Base Plate on Microstructure and Mechanical Strength of Aluminum–Stainless Steel Explosive Cladding

In this study, aluminum 6061 (AA6061) plates are explosively cladded with stainless steel 304 (SS304) plates having ‘V’ and dovetail grooves machined on the mating surfaces of the stainless steel plates. The results are correlated with the outcome of Al 6061-groove less SS 304 explosive clads. The machining of the grooves promotes undulating interfaces, due to the enhancement in the kinetic energy utilization. Though, a slender molten layer formation comprising of FeAl2, Al3Fe and Al5Fe2 compounds are observed in the crest of the grooves, mechanical strength of the clads increases because of the enhanced integrity across the grooved region. Micro-hardness increases in the closer proximity of the collision surface, while the tensile and shear strength of the AA6061-grooved SS304 explosive clads are higher than the conventional Al-groove less steel explosive clads. Of the two grooved base plates attempted, V-grooved base plate exhibits superior microstructure and strength characteristics. Fracture surface of both tensile and shear test specimens exhibits ductile and mixed mode of fracture at different locations of the clad.

Production of ship steel—titanium bimetallic composites through explosive cladding

Titanium was combined with ship steel sheet through the explosive cladding technique using different explosive ratios. The effects of the explosive ratio on the microstructure, mechanical and corrosion properties of the ship steel-titanium bimetallic composites were investigated. The microstructural characterization of the bimetallic composites was studied by optical microscopy (OM), scanning electron microscopy (SEM) and energy-dispersive spectrometry (EDS). The mechanical properties were determined through tensile-shear, impact toughness, bending, twisting and microhardness testing, while the corrosion behaviour was examined using neutral salt spray (NSS) tests. The microstructure studies revealed that a wavy joining interface was attained at higher explosive ratios, while a completely smooth interface was achieved at the lowest explosive ratio. In the microhardness tests, the highest hardness values were attained from both sides of the joining interface. Conclusions of the mechanical tests separation did not occur in the interfaces of the bimetallic composite specimens. In the corrosion test, the titanium was found to have higher corrosion resistance than the ship steel sheet. It was concluded that the mechanical and corrosion properties of the ship steel sheet can be enhanced by explosive cladding with titanium.

Study on modalities and microdefects of Al-Cu bimetallic tube by underwater explosive cladding

In this study, a screwed copper tube was cladded an aluminum tube by a new explosive cladding method. To study the modalities of the bonding interface, a light microscope was used to observe the bonding interface. To expose the weak position of the interface, a three-point bending test was conducted under extreme condition. Then the BSE (Backscattering Electron) images of the bent interfaces were obtained. Meanwhile, the EDS (Energy Dispersive Spectrometry) analyses of the melted zone were performed. The results of the light microscopic observations show that there are four bonding modalities on the interface. They can be summarized to two bonding modalities: direct bonding and bonding with the melted zone. There are no macro cracks on the interface of the bent specimens, which represents a reliable joining generally. The elastic modulus of Al-Cu bimetallic tube along the axial direction is 85.2Gpa. The BSE images, the EDS analyses and the microhardness tests show the direct bonding with some characteristics of the micro wavy interface is a pretty nice bonding pattern. The melted zone composed of CuAl2 is a weak bonding pattern, which may affect the mechanical property of the joint.

Effect of wire mesh interlayer in explosive cladding of dissimilar grade aluminum plates

Explosive cladding of Al 5052-Al 1100 plate, interfaced with a stainless steel wire mesh interlayer, is attempted. Loading ratio and standoff distance were varied. An increase in loading ratio (R) and standoff distance (S) enhances the plate velocity (Vp), dynamic bend angle (β) and pressure developed (P). The interface morphology of the explosive clads confirms strong metallurgical bond between the wire mesh and aluminum plates. Further, a smooth transition from straight to undulating interlayered topography is witnessed. The introduction of a wire mesh, as interlayer, leads to an improvement in mechanical strength with a slender reduction in overall corrosion resistance of the “explosive clads”.

Influence of Explosive Ratio on Morphological and Structural Properties of Ti/Al Clads

The current work focuses on the effect of explosive ratio R on the comprehensive properties of Ti/Al clads manufactured via explosive welding. The lower and upper limits of explosive ratio, namely R1 and R2, were determined according to the R–δf (flyer plate thickness) welding window. Two TA2/1060 explosive cladding plates were successfully manufactured at the different explosive ratios. Microstructure investigation was conducted by optical microscopy (OM), scanning electron microscopy (SEM), and energy dispersive spectrometer (EDS). The small wave bonding interface was observed at R1, where the vortex structure containing the ingot structure appeared periodically. The bonding interface presented a big wave bonding morphology and a locally continuous melting layer at R2. Many prolonged grains and adiabatic shear bands (ASBs) were found near the interface for a greater explosive load. Intermetallic compounds were formed in the bonding zones of the two plates. The thickness of element diffusion area increased with an increasing explosive ratio. Comparative tests of mechanical properties indicated that the tensile shear strength at R1 was higher. The microhardness, tensile strength, and bending performance of the two plates are similar and acceptable. Tensile fracture analysis indicated the fracture mode at R1 was ductile fracture, while the explosive cladding plate at R2 had mainly ductile fracture with quasi-cleavage fracture as the supplement.

Inhomogeneous bonding state modeling for vibration analysis of explosive clad pipe

Early detection of damage bonding state such as insufficient bonding strength and interface partial contact defect for the explosive clad pipe is crucial in order to avoid sudden failure and even catastrophic accidents. A generalized and efficient model of the explosive clad pipe can reveal the relationship between bonding state and vibration characteristics, and provide foundations and priory knowledge for bonding state detection by signal processing technique. In this paper, the slender explosive clad pipe is regarded as two parallel elastic beams continuously joined by an elastic layer, and the elastic layer is capable to describe the non-uniform bonding state. By taking the characteristic beam modal functions as the admissible functions, the Rayleigh-Ritz method is employed to derive the dynamic model which enables one to consider inhomogeneous system and any boundary conditions. Then, the proposed model is validated by both numerical results and experiment. Parametric studies are carried out to investigate the effects of bonding strength and the length of partial contact defect on the natural frequency and forced response of the explosive clad pipe. A potential method for identifying the bonding quality of the explosive clad pipe is also discussed in this paper.