Explosive Cladding Research Articles

Modelling and measuring of temperature distribution in explosive cladded materials under induction heating

The work focuses on the modelling and experimental verification of induction heating systems with multilayered loads made of paramagnetic materials obtained through explosive cladding. The research is driven by the industry’s increasing interest in multilayered materials in electrical engineering and electronics. In this case, two- and three-layered configurations, as well as a cylindrical-shaped work coil, were considered. The main parameter subjected to verification was the surface temperature of the batch and its distribution. Due to relatively high temperatures, three measurement methods were used for temperature verification and effectiveness comparison: thermal imaging camera, pyrometer, and thermocouple. Additionally, the developed numerical models will provide a better understanding of the phenomena occurring in multilayered materials under the influence of rapidly changing electromagnetic fields and their impact on the heating process of the entire load. The article also addresses the issue of constructing models with a high discretisation level.

Characteristics of ejecta resulting from hypervelocity impact on Al/Mg explosive welding clad materials

In this study, we propose the use of a clad material, created from aluminum alloy A1100P-H24 and magnesium alloy AZ31B-H24 through explosive welding, as a Whipple shield for space applications. Two kinds clad materials with thickness ratios of Mg: Al = 0.5: 0.5 and Mg: Al = 0.7: 0.3 made from explosive welding, are compared to the current standard, the 1 mm thick A6061-T6 Whipple shield utilized in the international space station. By explosive welding low density, high specific strength, and high impact strength magnesium alloy with aluminum alloy, clad materials achieved 16.8% and 23.7% reduction in area density compared to A6061-T6. In the context of space debris mitigation, we performed hypervelocity impact tests on these clad materials. Detailed comparisons were made between the impact characteristics of the explosive welded clad materials and A6061-T6 by examining the perforation hole size and shape, and by collecting and analyzing the ejecta produced during impact. The experimental results revealed that the clad material with the thickness ratio of Mg: Al = 0.7: 0.3 experienced delamination at the material interface due to the penetration of projectile. On the other hand, the Mg: Al = 0.5: 0.5 clad material exhibited a perforation hole pattern comparable to that of monolithic aluminum and magnesium alloy materials. The cumulative number distribution of ejecta indicated that the clad material with a Mg: Al = 0.5: 0.5 ratio could reduce ejecta production. To further evaluate interface delamination, post-impact ultrasonic analyses were performed on the clad materials.

Izrada reaktora za proizvodnju hlor-dioksida od dvoslojnih ploča titan - čelik

Titanium has the widest application of all reactive metals. The basic properties of titanium are good corrosion resistance and an excellent strength-to-weight ratio. It is applied in: chemical industry, aviation, rocket technology, medicine, etc. With development of metallurgy of titanium production, its price became much more accessible, but it is still very high, the welding repair is therefore applied wherever possible. Welding is also significantly used for the production of machine parts. This paper presents a detailed procedure of reactor vessel production for obtaining chlorinedioxide (CiO2) in the chemical industry PULP-Viskoza. The reactor is made from a titanium-clad steel plate. Explosive cladding and the principle of clad welding (bonding of elements) are described. Prior to the onset of the reactor production, the tests of titanium/steel bonding by explosive cladding were made for defining the required parameters. The plates were cut from the trial cladding, and inspected by ultrasound and penetrant testing followed by trial welding, resulting in the final selection of welding parameters. Relaxation of cladding from the residual tension was made in the furnace without air removal in order to determine the condition in which the titanium will be after heat treatment.

Prediction of aluminium–stainless steel explosive clad strength through machine learning

Prediction of aluminium–stainless steel explosive clad strength through machine learning

Thermo-Structure Approach to Dissimilar Explosive Cladding with Interlayer

A thermodynamic model capable of predicting the change in internal energy, work done, and thermal energy required during aluminum-stainless steel explosive cladding is presented. The mathematical model is instrumental in determining the temperature and pressure developed at the interface, which characterizes the interface microstructure, compared with the numerical simulation. Numerical simulation is implemented by the Smoothed Particle Hydrodynamics method available in ANSYS Autodyn. Furthermore, the effect of different interlayers, such as Al 1100, copper, and SS 304, on kinetic energy utilization and deformation work is discussed. The increase in ram tensile and shear strengths is also reported.

Experimental test and simulation calculation of fatigue properties of aluminum–titanium-steel explosive welded connector under tension-compression cyclic loading

The three-layer clad plate (aluminum alloy layer/commercial pure titanium layer/CCSB steel layer) was prepared by explosive welding as marine transition connector. The fatigue properties of clad plate were studied by experiment and finite element simulation. The fatigue limit and S–N curve were obtained by axial high-cycle fatigue test under tension-compression loading. The up-and-down method and group method were used respectively. Combining Static Structural module and DesignLife module based on the ANSYS Workbench Platform, the stress distribution, safety factor and fatigue life of clad plate under different loads were calculated. The results show that fatigue limit of Al–Ti-steel clad plate is 55 MPa, and the fatigue fracture mainly occurs in the 104∼106 cycles period in the stress range of 65 MPa∼100 MPa. The maximum relative error of fatigue life is 7.05%, and the relative error of fatigue limit is 0.45% between model and test fitting values. The results of finite element simulation have good agreement with the results of experimental method, which proves the feasibility and reliability of finite element simulation to analyze and forecast fatigue property of explosive welded clad plate. The position of the stress concentration is at the connection part between steel and pure titanium, while fatigue fracture occurs in the 3003 aluminum alloy layer because of the low tensile strength. Improving the tensile strength of Al-steel joint material is a key measure for solving the fracture problem of hull foundation.

Performance of ANN in Predicting the Tensile and Shear Strength of Al-Steel Explosive Clads

In this study, an artificial neural network (ANN) model is created to predict aluminium-stainless steel explosive clads' tensile and shear strengths. The parameters for the explosive cladding process, such as the loading ratio (mass ratio of the explosive and the flyer, 0.6-1.0), standoff distance (5-9 mm), preset angle (0°-10°), and groove in the base plate (V/Dovetail), were altered. The ANN algorithm was trained in Python using the tensile and shear strengths gathered from 80% of the experiments (60), trials, and prior results. The constructed model was evaluated utilizing the remaining experimental results. The ANN model successfully predicts the tensile and shear strengths with an accuracy of less than 10% deviation from the experimental result.

Application of Deep Learning Techniques to Predict the Mechanical Strength of Al-Steel Explosive Clads

In this study, the tensile and shear strengths of aluminum 6061-differently grooved stainless steel 304 explosive clads are predicted using deep learning algorithms, namely the conventional neural network (CNN), deep neural network (DNN), and recurrent neural network (RNN). The explosive cladding process parameters, such as the loading ratio (mass of the explosive/mass of the flyer plate, R: 0.6–1.0), standoff distance, D (5–9 mm), preset angle, A (0–10°), and groove in the base plate, G (V/Dovetail), were varied in 60 explosive cladding trials. The deep learning algorithms were trained in a Python environment using the tensile and shear strengths acquired from 80% of the experiments, using trial and previous results. The remaining experimental findings are used to evaluate the developed models. The DNN model successfully predicts the tensile and shear strengths with an accuracy of 95% and less than 5% deviation from the experimental result.

Explosive cladding of Monel alloy tube and copper rod

Explosive cladding parameters directly affect the interfacial bonded quality, and they are crucial for choosing appropriate cladding parameters for different metal combinations. The "explosive cladding window" of Monel alloy/Cu bimetallic bonded rod was designed utilizing MATLAB software, and the Monel alloy/Cu explosive cladded rod with wavy interfaces was successfully fabricated by applying optimal cladding parameters. On this basis, the interfacial microstructure and mechanical properties of Monel alloy/Cu explosive cladded rod were investigated. The TEM results showed that the interface bonded region consists of three parts: the molten zone (amorphous, nanosized Ni3Si phases), the heat-affected zone (recrystallized grains), and the deformation zone (microbands). Deformation twins were present in the matrixes of Monel alloy and Cu. The number, morphology, and distribution of deformed twins on the two sides are different due to the different stacking fault energies of Monel alloy and Cu. Compression-shear separation tests revealed that the fracture occurred on the Cu side, indicating the interfacial bonded strength is higher than that of the Cu matrix. In addition, the interfacial hardness was lower than on the Monel alloy side but higher than on the Cu side, which is associated with severe deformation and recrystallization near the interface. This work provides a method combining theoretical design and experimental research for choosing the process parameters of bimetallic rods, which provides an important reference for optimizing explosive cladding parameters of heterogeneous metal and facilitates the wide application of explosive cladding techniques.

Effect of different interlayer on Al 5052/SS 316 explosive cladding

The study presents the microstructural and strength characteristics of Al5052/SS316 explosive clads interlaced with different interlayer (aluminium 1100/SS 304/copper) by varying standoff distance (6 and 8 mm), loading ratio, R (mass of explosive/mass of flyer plate: 0.6 and 0.8) and preset angle between flyer and interlayer (6 and 8°), A. The interface microstructure shows the transformation of an uninterrupted melted layer formed in conventional cladding (no interlayer) into a thin or no reaction product clad, when an interlayer is introduced. Similarly, the kinetic energy utilization (1.26 –1.79 MJ/m2) and deformation work (0.76 –1.10 MJ/m2) during explosive cladding increase. The explosive clads having an interlayer exhibit higher mechanical strength than the interlayer less explosive clads and the highest strength (RTS: 263 MPa; Ss: 175 MPa) was witnessed for Al 5052/SS 304/SS316 explosive clads at higher parametric levels.

Preparation and Performance of ANPyO/Emulsion Explosive Composite Energetic System

AbstractIndustrial explosives with a low detonation velocity serve as the core‐driven energy source for explosive cladding, but have a limited pressure output. A composite energetic system containing high‐energy explosives/emulsion explosives can overcome this limitation. Accordingly, the search for high‐energy explosives with intrinsic safety features is key to achieving such systems. Therefore, in this study, 2,6‐diamino‐3,5‐dinitropyridine‐1‐oxide (ANPyO) with high‐energy‐insensitivity characteristics was selected as the energetic agent to prepare a composite energetic system with an ANPyO/emulsion explosive, and its safety and energy release effects were systematically studied. The experimental results showed that the content of ANPyO had a “linear” relationship with the apparent density of the developed composite energetic system, and had little effect on its impact and friction safety (the explosion probability was less than 10 %). In addition, the introduction of ANPyO did not have a significant impact on the detonation velocity of the composite energetic system, with an average detonation velocity of 2650 m ⋅ s−1. However, it did effectively improve the pressure output of the composite system. The peak pressure increased by 23.69 % from 27.27 kPa to 33.73 kPa, while the boosting rate increased by 88.09 % from 1256.68 kPa ⋅ s−1 to 2363.70 kPa ⋅ s−1. The improvement in the pressure output endowed the ANPyO/emulsion explosive composite energetic system with excellent work capacity, enabling T2/Q235 to compound well during explosive cladding. The above studies prove that this system can effectively maintain the relationship between the safety and energy output, positively contributing toward the development of explosive cladding technology.

Effect of annealing temperature on tensile fracture behavior of AZ31/6061 explosive composite plate

In this study, the first evaluated and analyzed the local strain evolution and macro fracture morphology of AZ31/6061 explosive composite plate during uniaxial tension by the digital image correlation (DIC) method. The materials used are double-layer AZ31/6061 composite plates prepared by the explosive welding process. In order to meet the subsequent forming requirements, annealing at different temperatures is carried out. The fracture damage mechanism of AZ31/6061 explosive clad plate was comprehensively studied through mechanical tests at different annealing temperatures, microstructure characterization and fracture behavior analysis during the tensile process. The results showed that the thickness of the intermetallic compound at the interface increased with the increase of temperature, and the interface bonding strength reached the highest at 150 °C. Under the condition of 200 °C/2 h annealing, the composite plate has the best comprehensive properties, the tensile strength is 253.51 MPa, and the failure elongation is 25.16%. Combined with the SEM observation of tensile fracture and the evolution of strain distribution measured by digital image correlation (DIC), it is shown that the composite plate is mainly a brittle fracture mechanism before annealing and a ductile-brittle mixed fracture mechanism after annealing. Revealed the effect of temperature on the interfacial strengthening mechanism and fracture behavior of Mg/Al composite plate during fracture.

Interface Zone Microstructure of the Explosively Cladded Copper on Steel

Interface Zone Microstructure of the Explosively Cladded Copper on Steel

Elucidation of the joining and interface mechanism of lightweight difficult-to-weld materials joined by explosive impact force

Explosive welding can be used to join materials using controlled explosions, creating materials with desirable properties. Assistant Professor Mami Mihara-Narita, Department of Physical Science and Engineering, Nagoya Institute of Technology (NIT), Japan, is exploring the potential of joining technology by explosive welding for the multi-materialism of lightweight materials such as magnesium alloy and aluminium alloy and evaluating their characteristics for practical use. She hopes that her work will contribute to the weight reduction of transportation materials, as well as benefiting transportation equipment and clean energy materials. Mihara-Narita is collaborating closely with Professor Yoshimi Watanabe and Associate Professor Hisashi Sato from NIT, and Dr Yasumasa Chino and Dr Hisashi Mori from the National Institute of Advanced Industrial Science and Technology (AIST and UACJ corporation) in this work. The team is also performing characteristic analysis of explosive welded materials, using a transmission electron microscope to observe interfacial microstructure. The researchers are also evaluating joint strength by shear test, measuring hardness and micro deformation by nanoindentation method and measuring residual stress by X-ray diffraction and neutron diffraction method. In addition they are investigating fatigue strength in order to ensure materials are suitable for use in transportation equipment. Fatigue strength will continue to be a key focus for the researchers moving forward, and they will also be performing data analysis of their data on explosive welding conditions, metallographic structure and various properties of explosive welding clad material.

Soft computing approaches for comparative prediction of ram tensile and shear strength in aluminium–stainless steel explosive cladding

Soft computing approaches for comparative prediction of ram tensile and shear strength in aluminium–stainless steel explosive cladding

Microstructure, strength and welding window of aluminum alloy−stainless steel explosive cladding with different interlayers

Aluminum 5052 (Al 5052)−stainless steel 316 (SS 316) plates were explosively cladded with Al 1100, pure copper and SS 304 interlayers. The operational parameters viz., standoff distance, explosive mass ratio (mass ratio of the explosive to the flyer plate) and inclination angle were varied and the results were presented. The advent of interlayer relocates the lower boundary of the welding window, and enhances the welding regime by 40%. A triaxial welding window, considering the influence of the third operational parameter, was developed as well. Use of interlayer transforms the continuous molten layer formed in the traditional Al 5052−SS 316 explosive clad interfaces into a smooth interface devoid or with a slender presence of intermetallic compounds. The microhardness, ram tensile and shear strengths of the interlayered clads are higher than those of the traditional explosive clads, and the maximum values are witnessed for stainless steel interlaced Al 5052−SS 316 explosive clads.

РОЗРАХУНОК НАПРУЖЕНО-ДЕФОРМОВАНОГО СТАНУ ПЛАКУЮЧОГО ШАРУ ПРИ ПЛАКУВАННІ (ЗВАРЮВАННІ) ВИБУХОМ

Purpose. Development of a mathematical model of the process of elastoplastic deformation of the cladding layer of a layered workpiece during welding (cladding) by explosion with the formation of the objective function of optimal deformation and establishing a relationship between the parameters of welding (cladding) by explosion and the shear bond strength of the layers and the wear resistance of the cladding layer. Methodology. The solution to the problem of elastoplastic deformation is carried out using the equations of the flow theory and the nodal calculation scheme. The required deformation values are determined at the nodal mass points of the computational grid. At each moment of time, the positions of the nodes of the cladding workpiece, thrown under loading by a traveling pressure wave, are de-termined. Deformations and their intensity are determined by the position of the nodes. The task of determining the re-quired parameters of explosion welding (cladding) is reduced to the task of mathematical programming. The objective function is minimized on a family of curves, the arguments of which are the explosion welding (cladding) parameter and the welding gap. The interaction of the cladding workpiece with the pressure wave generated during the detonation of the explosive is determined by the dependences of the pressure of the detonation products, the mass velocity of the cladding workpiece and the shock wave velocity at the moment the shock wave reaches the free surface on the parame-ters of the explosion cladding (welding) with subsequent calculation of the stress-strain state of the workpieces. Accord-ing to the optimal parameters of explosion welding (cladding), a probabilistic assessment of the shear bond strength of the layers is carried out. If the strength is insufficient, the parameters are adjusted. Findings. As a result of numerical modeling, the calculation of the deformed state of the projectile is carried out. The parameters of explosion welding (cladding) are determined, at which the intensity of deformations of the cladding layer corresponds to the limit uniform ones. Based on the obtained parameters of explosion welding (cladding), the calculation of the shear strength of the layer joint was performed. Originality. For the first time, a model has been developed for the optimal deformation of the cladding layer during explosion welding (cladding) of wear-resistant compositions. The target function and the optimal process parameters have been established. A method is proposed for calculating the weighting coefficients of the objective function for multi-criteria multilevel optimization. Practical value. Recommendations for industrial application were developed and modes of explosion welding (cladding) were tested to obtain wear-resistant compositions of aluminum alloy with carbon steel.

Tensile and shear strength evaluation in joining dissimilar plates of mild steel with aluminum alloy through explosive cladding approach

Explosive cladding is known for its ability to join a wide variety of metals that other welding methods cannot do. In this present work, the weldability of aluminium alloy and mild steel plates and their bonding strength through an explosive cladding process investigation is performed. Experiments are conducted in the open air using Gelatin (SG-90) variety explosive having a detonation velocity of 3400 m/sec. Experimental trials for single replications were adopted. Ram tensile test has been carried out to determine the bonding strength. The effects of angle of inclination, loading ratio and stand-off distance on the weld strength were analyzed. The possibility of obtaining a sound weld depends on the limiting conditions of the above parameters. The microstructure of the explosive clad joints is studied for varying process parameters which shows a wavy profile that produces higher strength. The strength of the weld in both tensile and shear strength obtained is good and is within the acceptable range. An increase in strength of welded joints is obtained for higher parameter range.

Optimization of operational parameters in Al5052-SS316 explosive cladding

Optimization of operational parameters to achieve higher tensile strength in Al5052-SS316 explosive cladding is attempted. The operational parameters viz., standoff distance, loading ratio (mass of explosive/mass of flyer plate), inclination angle and interlayer were varied in three levels, and their optimum levels were determined. Analysis of variance (ANOVA) concluded that all the chosen operational parameters influences the tensile strength of the dissimilar explosive clads with different interlayer. The maximum tensile strength is obtained for the experimental condition having stainless steel interlayer, loading ratio-1.0, initial angle-100 and standoff distance-10 mm. In addition, a mathematical model is formulated to estimate the tensile strength of different interlayered Al 5052-SS 316 explosive clads.

Optimization of the combined explosion hardening processes

The proposed method for calculating the loading parameters makes it possible to determine the wear parameters after explosion hardening. The calculation method is simple and less time consuming compared with calculation methods that involve the use of nonlinear programming methods. The main methods of increasing the wear resistance of mining equipment parts using explosion methods are generalized. The reserve for increasing the wear resistance consists in the optimization of deformation parameters during the power and thermal intensification of processes and the development of new methods and technologies of hardening. The factors (parameters) of the studied processes: explosive cladding, alloying, hardening, are formulated. Optimization of the processes under consideration is possible by decomposing the process into simpler ones with subsequent optimization of the parameters of these processes and the synthesis of the obtained solutions. For the first time, a solution to the multicriteria problem of two-stage explosion hardening is presented. It is proposed to split the process into simpler ones. Optimization criteria are proposed for each of the simplified processes. The problem is reduced to a conditional extremum problem, which is solved by composing the Lagrange function. By transforming the wear equation, the optimal ratio of strength and ductility for parts operating under abrasive wear conditions is determined.