Explosive Welding Research Articles

Evaluation of corrosion properties of TA2-Q345 explosive composite plate at different heat treatment temperatures

This study investigated the effects of post-weld heat treatment (PWHT) at 500 °C, 600 °C, 700 °C, and 800 °C on the microstructure and corrosion performance of the TA2-Q345 explosive composite plate, with TA2 as the flyer plate and Q345 as the base plate. X-ray diffraction (XRD), optical microscopy (OM), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analyses were performed, alongside electrochemical experiments. The explosive welding interface of the TA2-Q345 composite plate exhibited a characteristic wavy structure, which indicated high welding quality. The XRD results indicated that the PWHT temperature significantly affects both the phase structure and the intensity of the diffraction peaks of the oxide film. Additionally, the porosity calculations demonstrated that the sample subjected to PWHT at 500 °C exhibited the lowest porosity in the surface oxide film, resulting in a denser oxide film that effectively enhanced corrosion resistance. However, as the temperature continued to rise, defects such as craters, bulges, and delamination between the oxide film and the titanium matrix were observed. The results of the electrochemical analysis indicated that, compared to untreated samples, the PWHT samples demonstrated improved corrosion resistance. Specifically, the sample with PWHT at 500 °C has the lowest corrosion current density (icorr) of 6.1892E-06 A/cm2, while the untreated sample has the highest icorr of 6.3577E-05 A/cm2, indicating that 500 °C is the optimal temperature. The corrosion process involved the hydrolysis of titanium chloride to form a TiO2 film and localized corrosion of the TiO2 protective film. The corrosion products composed of mainly C, O, and Ti were dispersed on the surface of PWHT samples.

Design of explosively welded Fe–Al multilayer laminated composite pipes: A critical microscopy analysis of stand-off distance and post-weld heat treatment effects on interface properties

This study examined the microstructure and mechanical properties of explosively welded (EXW) Fe–Al multilayer laminated composite pipes, specifically SS321/AA1050/AA5083, with varying stand-off distances (SD) and post-weld heat treatments (PWHT). Findings revealed that higher collision forces at higher-SD produced a wavy interface with finer grains at the AA1050/AA5083 interface. In contrast, lower-SD yielded a smooth, flat interface. At the SS321/AA1050 interface, collision energy resulted in the formation of an uneven composite reaction layer comprising multiple intermetallics. Analysis of the SS321/AA1050 interface revealed that an increase in the PWHT temperature results in diffusion toward the reaction layer, transforming the unevenly Al-rich and Fe-rich phases into a uniform Al85(Fe,Cr,Ni)15 solid solution. The increase in the fraction of this phase made the reaction layer more brittle. At the AA1050/AA5083 interface, PWHT at higher temperatures caused a significant hardness decline extending further from the interface in samples with higher-SD. On the SS321 side of the laminated composite, higher SD resulted in higher kernel average misorientation (KAM) and increased hardness. Despite a decrease in hardness after PWHT at 350 °C, the hardness gradient from the matrix to the interface in laminates with higher SD remained relatively unaffected, whereas the lower SD counterparts experienced a noticeable stress relief.

РЕНТГЕНОСТРУКТУРНЫЕ ИССЛЕДОВАНИЯ СВАРЕННОГО ВЗРЫВОМ МЕДНО-СТАЛЬНОГО БИМЕТАЛЛА ПОСЛЕ ТЕРМИЧЕСКИХ ВОЗДЕЙСТВИЙ

The article presents the results of studies of diffusion processes in the joint zone of the bimetallic copper M3 + steel 30CrMnSiA after explosion welding and subsequent thermal effects at 880 °C with a holding time of up to 10 hours, 1000 °C with holding times of 24, 50, 100 hours and 1050 °C with a holding time of 1 hour. It is shown that the intensification of diffusion processes of steel into copper and copper into steel near the joint boundary with the formation of solid solutions causes a significant development of the thin structure characteristics: an increase in the level of relative lattice deformation and a refinement of mosaic blocks.

Investigating the Effect of Explosive Welding Variables on the Corrosion Behavior of Copper–Aluminum–Copper in the Salt Environment

Investigating the Effect of Explosive Welding Variables on the Corrosion Behavior of Copper–Aluminum–Copper in the Salt Environment

Experimental and numerical study on ballistic impact behavior of explosively-welded double-layered Weldox700E targets against ogival-nosed projectiles

In this work, explosive welding technique was used to fabricate 2 mm + 2 mm thick double layered Weldox700E steel targets. The bonding interface exhibited wave-shaped patterns without obvious micro-defects, grain refinement and grain elongation were observed. With specially designed shear specimen and tensile specimen, Ultimate stresses of the bonding interface under shear and tensile loadings were measured to be 526 MPa and 683 MPa, respectively. Ballistic impact tests against ogival-nosed projectiles were conducted on both explosively welded double-layered targets and double-layered contact targets. Ballistic limit velocities of the two target configurations were respectively 225.32 m/s and 203.98 m/s , with the former being 10.5 % higher than the latter. For both target configurations, localized bulging and petal-shaped cracking were observed; specially, welded bonding interface remains well bonded even after perforation of the projectile. Combining experimental results and numerical simulations, it was found that the explosively welded double-layered targets exhibited better ballistic performance than double-layered contact ones. The good welded bonding interface provides a better overall deformation capability for the explosively welded double-layered target, which is an important reason for the improved ballistic performance of the target. Although hardness tests show that there is a significant hardened layer in the explosively welded double-layered target, and the hardness value can reach up to 409.4 HV. However, the thin hardened layer cannot significantly improve the ballistic performance of the explosively welded double-layered target in the high-speed impact process of the projectile.

Study of microstructure evolution in the aluminum‒magnesium alloy AlMg6 after explosive welding and heat treatment

Study of microstructure evolution in the aluminum‒magnesium alloy AlMg6 after explosive welding and heat treatment

Explosively welded SLM-AlSi10Mg/SLM-SUS316L: Unveiling superiority of interlayer welding for enhanced mechanical properties

Following the advent of three-dimensional (3D) printing technology, multi-material 3D printing has garnered significant attention due to its potential to enhance the flexibility and development of high-performance 3D printing materials. This study investigated the application of explosive welding to create multi-material 3D printed structures. Specifically, we explored the use of direct and interlayer explosive welding to fabricate SLM-AlSi10Mg/SLM-SUS316L explosive composites with the aim of further improving material properties. Our primary objective was to explore the unique interfaces and mechanical characteristics of 3D printed materials subjected to explosive impact loading. This study provides a new idea of 3D printing multi-materials, which is of great significance for the development of both explosive welding and 3D printing. The results demonstrated the feasibility of using explosive welding to create multi-material composites from 3D printed metals, including both direct and interlayer welding of SLM-AlSi10Mg/SLM-SUS316L. Interlayer welding exhibited superior mechanical performance compared to direct welding, with a 70%–250% increase in strength observed in the macro tensile shear test. Additionally, samples fabricated with a 40 mm explosive thickness displayed more stable and exceptional performance in the micro tensile test. Corrosion testing and X-ray computed tomography (XCT) analysis were employed to investigate the distribution of pores within the 3D printed materials.

Study of Structure Formation in Multilayer Composite Material AA1070-AlMg6-AA1070-Titanium (VT1-0)-08Cr18Ni10Ti Steel after Explosive Welding and Heat Treatment

Multilayer composite materials, consisting of layers of aluminum alloy and steel, are used in the manufacturing of large engineering structures, including in the shipbuilding and railcar industries. Due to the different properties of aluminum alloys and steels, it is difficult to achieve high-strength joints by conventional welding. Therefore, these joints are produced by explosive welding. In the present work, the structure of a multilayer material, AA1070-AlMg6-AA1070 (aluminum alloys)-VT1-0-08Cr18Ni10Ti (steel), was investigated after explosive welding and heat treatments were performed under different conditions. The microstructure of the AlMg6 layer at the AlMg6-AA1070 interface consists of shaped anisotropic grains extending along the weld interface. The AA1070 layer is enriched with magnesium due to its diffusive influx from AlMg6. In the AlMg6 and VT1-0 layers, adiabatic shear bands are found that start at the weld interface and propagate deep into the material. The optimal temperature for the heat treatment is 450–500 °C, as internal stresses are reduced at this temperature and the grain structure of the AlMg6 layer is not coarse. Tear strength testing revealed that the tear strength of the composite material after explosive welding was 130 ± 10 MPa, which exceeded the strength of the AA1070 alloy.

Study on explosive welding A7075 and Ti–6Al–4 V with aluminum or copper interlayer

Study on explosive welding A7075 and Ti–6Al–4 V with aluminum or copper interlayer

Explosive welding of TA2-SiC-AW5083 composite armor

This study investigates the use of explosive welding to encapsulate SiC between TA2 and 5083, aiming to achieve large-area, high-efficiency, and low-cost fabrication of ceramic composite armor. A new weldability window was established, and six configurations of ceramic composite armor were devised. Ten sets of experiments were conducted to explore the influence of explosive welding parameters, ceramic fracture, and different configurations of composite complate on mechanical properties, macro-deformation, welding interface morphology, and energy absorption and conversion. The research revealed that the fracture of ceramic influences the welding quality, the propagation of the blast wave, and the kinetic energy utilization of the flying plate, while the crevices between the ceramic and the groove on the base plate do not influence the welding quality. When the ceramic remains intact, the kinetic energy utilization rate of the flying plate can be calculated using the η = E1(1-A1/A)/Ef, and when the ceramic penetratively fractures, the kinetic energy utilization rate of the plate can be calculated using the η=(E1-E4) (1-A1/A)/Ef. Finally, we recommend adding a suitable interlayer as a buffer between the flying plate and the ceramic, and the static parameters for explosive welding should strictly adhere to the “Lower bound principle."By analyzing the energy conversion and absorption during the explosive welding process, the macro-deformation and mechanical properties of the composites, the interface morphology, and the level and characteristics of the ceramic fracture, the energy source of the ceramic fracture was found, and the effects of ceramic fracture and structural characteristics of composites on gap airflow, kinetic energy utilization of face plate, explosive wave propagation path, and welding quality were analyzed. Finally, we propose that the explosive welding static parameters of ceramic composite armor should strictly adhere to the " The principle of lower explosives limit."

Mechanical Properties and Corrosion Behaviour of Copper/Titanium Composite Plates made by Explosive Welding after Heat Treatment

Mechanical Properties and Corrosion Behaviour of Copper/Titanium Composite Plates made by Explosive Welding after Heat Treatment

Investigation on structural feature and bonding performance of Hastelloy foil/steel explosive welding composites under different explosive loads

Hastelloy foil/steel composite is of most interest in many industrial fields, as it has competitive advantages of excellent corrosion resistance and low cost. Due to the low thermal conductivity and thermal hardening property, traditional fusion-based connection methods fail to provide high-quality Hastelloy/steel composites. Here an improved explosive welding was introduced to prepare this composite, and the effect of the explosive amount was carefully investigated. The characterizations (including optical microscopy (OM), electron backscatter diffraction (EBSD), bending, nanoindentation, and electrochemical corrosion) were conducted to understand the bonding properties, and Smoothed Particle Hydrodynamics (SPH) simulation was used to investigate transient interface behavior. It was found that the self-developed explosive welding was a suitable method to produce superior Hastelloy/steel composites. Under reasonable welding parameters, both the surfaces of Hastelloy and Hastelloy/steel interface exhibited ideal welding patterns without defects, and the composite remained intact under 90° bending loading. The explosive load is a crucial factor determining bonding properties, and the undesirable features like wrinkles and melting area were found to be positively correlated with the explosive load, which reduced the corrosion resistance. This comprehensive research enabled to provide a new perspective for Hastelloy/steel preparation and improve the understanding of explosive welding process behavior.

A novel solid-state metal additive manufacturing process – Laser-induced Supersonic Impact Printing (LISIP): Exploration of process capability

Solid-state metal additive manufacturing (AM) techniques offer unique capabilities for direct printing of metallic materials towards a variety of applications. In this work, we developed a novel solid-state metal AM process, named laser-induced supersonic impact printing (LISIP), in which the laser shock-induced impact loading was utilized to trigger the adiabatic shearing phenomenon at metal-metal interfaces towards solid-state three-dimensional (3D) printing of metallic materials. The design of LISIP was inspired by cold spray, explosive welding, and laser impact welding. An experimental investigation was conducted to explore the process capability of LISIP, with a focus on 3D micro-lamination of metallic structure, AM of dissimilar materials, and printing-on-demand direct writing at various length scales from micrometer to centimeter. Steel, copper, aluminum, titanium, and magnesium alloys were used as foil and/or substate for experimentation. Moreover, the microstructure at bonding interfaces were characterized to understand the microstructure evolution as induced by adiabatic shearing. The bonding quality was evaluated using the lap shear test. The mechanisms involved in LISIP including the laser-matter interaction and adiabatic shearing bonding were investigated using first-principles modeling and finite element method simulation. In addition, the technical challenges, scientific knowledge gaps, future research directions, and potential applications of LISIP were deliberated. We envision that the findings and knowledge gained in this work will serve as the first milestone towards the establishment of LISIP for broader impacts.

Insight on Interfacial Microstructure and Corrosion Characteristics of Mg/Al Explosive Welded Composite Plates

Interfacial corrosion performance is crucial to the reliability of Mg/Al explosively welded composite plates. Nevertheless, more understanding is required concerning such interfacial corrosion. In this work, a combination of numerical simulation and experimental investigation was used to clarify the microstructure evolutions of AZ80‐Mg alloy/1060‐Al explosively welded composite plate. The formation of interfacial wave structure and the thermodynamic state were insighted through numerical simulation, which further enhanced the correlation between the interfacial microstructural heterogeneities and the interfacial corrosion characteristics. Galvanic corrosion was produced by the significant potential difference between the AZ80‐Mg and 1060‐Al, with multiple micro‐galvanic couples in the vortex zone. The corrosion occurred near the interface and gradually advanced away from the interface. After 1 h, the composite plates exhibited severe corrosion with deep pits on the Mg side, while the Al side was less affected. Within the vortex, however, the Mg‐rich region underwent little corrosion, whereas the Al‐rich region underwent significant corrosion, attributed to the increase in pH value caused by the Mg corrosion.

Wettability and reactivity of liquid aluminium and highly deformed steel

The high-temperature liquid Al - solid S355J2N steel interaction was studied using a modified wettability test. A sessile drop method with a capillary purification procedure was employed for the first time, involving non-contact aluminium isothermal heating followed by the dropping of a pure liquid Al drop onto the severely deformed steel substrate and isothermal contact heating of Al with steel. The calculated contact angles and wetting kinetics curves demonstrated a good spreading and wetting of the investigated system. Scanning electron microscopy investigations played an important role in interpretation of the microstructural characteristics of the specimen, especially those located at the drop/substrate interface. The electron backscattered diffraction measurements allowed to characterize the microstructure of the interface zone to obtain more detailed information about the grain size, type of the intermetallic phases: θ-Al13Fe4, Fe2Al5, FCC Al and ferrite and their distribution in the neighborhood of the interface zone. These intermetallics were also confirmed via transmission electron microscopy studies coupled with energy-dispersive X-ray spectroscopy analysis of the drop/substrate interface. Research findings provide valuable insights into the liquid Al and steel interaction during the explosive welding process, where the local melting of metal takes place at the interface of colliding plates, strongly deformed due to the collision.

Friction Stir Welding Benefits Technique over Other Welding Techniques of Dissimilar Metals

Abstract: Due to the low heat input situation, solid state welding (SSW) has demonstrated higher potential for integrating a variety of equivalent and dissimilar material combinations. The temperature stays below the melting point of the source materials throughout the solid-state welding process. Compared to fusion welding, solid state welding offers the highest quality. Aeronautics, nuclear, space, and aviation are just a few of the industrial production sectors that utilize the solid-state welding technology. Diffusion welding, explosion welding, friction welding, forge welding, cold welding, role welding, hot pressure welding, and ultrasonic welding are just a few of the SSW techniques covered in the current article. This study looks at a variety of SSW kinds and solid-state welding applications. This study examines many types of SSW and the applications of solid-state welding. Current Study includes the pros and cons of other welding techniques over friction stir welding.

Friction Stir Welding Benefits Technique over Other Welding Techniques of Dissimilar Metals

Abstract: Due to the low heat input situation, solid state welding (SSW) has demonstrated higher potential for integrating a variety of equivalent and dissimilar material combinations. The temperature stays below the melting point of the source materials throughout the solid-state welding process. Compared to fusion welding, solid state welding offers the highest quality. Aeronautics, nuclear, space, and aviation are just a few of the industrial production sectors that utilize the solid-state welding technology. Diffusion welding, explosion welding, friction welding, forge welding, cold welding, role welding, hot pressure welding, and ultrasonic welding are just a few of the SSW techniques covered in the current article. This study looks at a variety of SSW kinds and solid-state welding applications. This study examines many types of SSW and the applications of solid-state welding. Current Study includes the pros and cons of other welding techniques over friction stir welding

Parameter-determined interface morphologies and properties of explosively-welded Cu–Ni–Si–Cr alloy composites

Six Cu–Ni–Si–Cr alloy composites are prepared by explosive welding with the designed parameters. Wavy interface containing the melted pockets and shrinkage cracks is always observed, refining the grains to just several micrometers with the localized deformation. Resultantly, the interface regions show higher hardness and yield strength than elsewhere, reaching HV 190 and over 400 MPa, respectively, but their plasticity is less than half that of the base-plate parts. Theoretical analysis successfully relates the area of the total disrupted regions including the interfacial molten and wavy zones in the composites linearly to the flyer-plate thickness (hf) and collision angle (β) as (hfsin2β2)2. For the composite fabricated at an impact velocity and angle of 310 m/s and 8.0°, respectively, strengthening mechanism calculation for its interface part reveals that grain boundary, dislocation and solid solution hardening are most effective and contribute 68 MPa, 370 MPa and 39 MPa individually, making the dislocation hardening dominant for the enhanced strength.

Joining of Al-Alloy Tubes by Carbon Steel Tubes using MPW Technique

Background/ Objectives: Joining aluminum alloys with low carbon steel (DC01) through fusion welding is a challenging task due to the occurrence of solidification defects like porosity, alloy segregation, and hot cracking. However, these issues can be addressed by employing solid-state welding techniques like explosive welding and MPW (magnetic pulse welding). MPW is a cost-effective and high-speed solid state welding method that involves creating joints in an overlap configuration. Methods: The MPW technique was employed to join dissimilar aluminum alloy AL 7075T6 hollow tube and DC01 steel rod in this study. A central composite design model was created to analyze the relationship between key MPW process parameters, including stand-off distance (SoD), overlap length, and discharge energy, and the bonding strength of the joints. Experimental setups were established and correlate with tensile-shear fracture load and interface hardness of the joints with the MPW process parameters. Findings: It is understood that the maximum TSFL of 2.404 kN was obtained under the welding condition of 23kJ discharge energy, 2.25 mm Stand-off distance, 8.5 mm overlap length, which is the optimum MP welding state for AA 7075 T6 with DC01 and confirmed by RSM. In addition, the cultivated connection can be aptly leveraged to anticipate the TSFL of MPW joints with a 95% confidence level. Novelty: The parametric mathematic samples were developed for forecasting TSFL of joints. The MPW parameters were optimized to enhance TSFL of joints. Aluminium alloys with low carbon steel joints were developed using MPW for cars and ships applications without fusion welding defects. Keywords: Magnetic Pulse Welding, Dissimilar Joint, (RSM) Response Surface Methodology, Tensile Shear-Fracture Load

Study on interface characteristics of TC4/7075 explosive welding based on molecular dynamics algorithm

The preparation of TC4/7075 composites for ultra-thin flyer plates is a significant challenge in the field of explosive welding. A weldability window for multi-layer metal explosive welding and a configuration for ultra-thin flyer plate explosive welding were established in this study. TC4/7075 composite materials were successfully prepared with a flyer plate thickness of only 0.3 mm. An analysis was conducted on the material bonding ability, element diffusion, crystal evolution, and microscopic morphology during the explosive welding process of TC4/7075, utilizing the weldability window, molecular dynamics algorithm, and electron backscattered diffraction testing. The results show that various dislocations are present at the interface, predominantly 1/6 ⟨112⟩ dislocations. Element diffusion primarily occurs during the unloading stage at high temperature and zero external pressure; the interface has the best bonding ability when titanium exhibits FCC lattice structure. The prepared composite material demonstrates high intra-grain and grain boundary stresses; the rolling texture is observed on the aluminum side while an equiaxed twin structure forms on the titanium side due to interactions between stacking faults, Stair-rod dislocations, and Hirth immovable dislocations.