The explosive welding is applicable in a wide variety of thicknesses, thermal, and mechanical properties, which has different applications. In this paper, Aluminum base composite as reinforcement with Steel Ck75 wire was manufactured by explosive welding. The Steel Ck75 wires were placed between two Aluminum plates. The Steel Ck75 wire was used to increase the strength of the Aluminum base composite. The parameters of the process were evaluated in detail. The excellent bonding quality of the interface without void can be represented in light microscope images. The weldability window and the simulation with the experimental data confirmed the fact that material and process parameters were well selected. The tensile tests showed that the reinforced composite showed higher strength than the unreinforced composite of about 8%.
La soldadura explosiva es aplicable en una amplia variedad de espesores, propiedades térmicas y mecánicas, por lo que tiene diferentes aplicaciones. En este trabajo, el compuesto de base de aluminio como refuerzo con alambre de acero Ck75 fue fabricado mediante soldadura explosiva. Los alambres de acero Ck75 se colocaron entre dos placas de aluminio. El alambre Steel Ck75 se utilizó para aumentar la resistencia del compuesto de base de aluminio. Los parámetros del proceso se evaluaron en detalle. La excelente calidad de unión de la interfaz sin vacíos se puede representar en imágenes de microscopio óptico. El intervalo de soldabilidad y la simulación con los datos experimentales confirmaron que los parámetros del material y del proceso estaban bien seleccionados. Los ensayos de tracción mostraron que el material compuesto reforzado mostró una resistencia mayor que el material compuesto no reforzado de aproximadamente un 8%.
Improving the mechanical properties of materials with using micro and nano fiber are widespread. Polymer based composites are normally reinforced with nano fiber like carbon nano tube and boron nitride and show increasing in mechanical properties (
The EXW is a type of welding process which can connect a base plate with a flyer plate by great pressure, that is manufactured by the detonation (
The EXW is a solid-state process, that applied a controlled explosive detonation to enforce two or three metals together at great pressure (
The EXW has that ability to bond different metals and has been used to manufactured some composite (
In the EXW, different phenomena such as plastic deformation of metals, great collision velocity, high temperature, and great-pressure states happen for a short time (
In the paper, pure Aluminum 1050 and Steel Ck75 chosen due to easier availability and their combination would permit the production of composite with good strength to weight ratio. The aim of this paper to manufacture Steel Ck75 wire reinforced Al base composite with improved mechanical properties. At present, the test of explosive welding was applied to validate the weldability window and simulation results.
The simulation of the EXW process was used by AUTODYN version 18. In the current model, Steel Ck75 wires for reinforcing and Al1050 was selected as the flyer plate and the base. A model for Al1050/SteelCK75/Al1050 explosive welding simulation is displayed in (
The default units are applied in the simulation, i. e., the mass in mg, the length is mm, the time is ms. The model is comprised of four materials, i. e., Al1050, Steel Ck75, Al1050 and Anfo (ammonium-nitrate/fuel-oil). The geometry sized are shown in
Materials | Geometry (mm) |
---|---|
Anfo (Explosive) | 250×250×60 |
Al 1050 (Flyer Plate) | 250×250×4 |
Al 1050 (Base plate) | 250×250×4 |
Steel Ck75 | D=0.9 |
The flyer plate, the base plate, and reinforced were modeled by Johnson-Cook (JC) equation (
where ԑ*
where, P is the pressure, ע is the specific volume, E is internal energy. The five constants are C1, C2, r1, r2, ω as displayed in
Materials | Al1050 | SteelCk75 |
---|---|---|
A | 110 | 103 |
C | 223 | 214 |
M | 197 | 120 |
Density /kg m-3 | 2710 | 7850 |
Hardness / Hv | 30 | 200 |
Poisson’s ratio | 0.33 | 0.33 |
Young’s modulus / GPa | 69 | 228 |
Bulk modulus / Gpa | 67.4 | 159 |
Melting | 923.15 | 1289 |
Explosive | Anfo |
---|---|
Detonation velocity/ m s-1 | 4160 |
Density /kg m-3 | 931 |
E/ G J m-3 | 2.48 |
/ Gpa | 49.46 |
/ Gpa | 1.891 |
3.90 | |
1.11 | |
ω | 0.33 |
The base of weldability window / criteria needs the collision angle (β) and the collision velocity (Vc). The weldability window is described by Six boarders (
where, Re is equal 10.616, Pf and Pp are the densities of Al1050 in Kg/m2 Hf and Hp are their Vickers hardness of Al1050.
The maximum collision velocity (Vc) for the weldability window is 1.2 times the sound velocity (
In which β is in radians, t is the thickness of Al1050 in m. The coefficient k3 can be calculated as:
where ע is Poisson’s ratio, E is the elastic modulus expressed in N/mm2 and ρ is the density in kg/m2.
The lower border is calculated by
k is 0.6 for high-quality, Hv is the hardness of Vickers of Al1050, ρ is the density for Al1050 in kg/m2.
In this paper, the Al1050 is the flyer plate, and the base plate and Steel Ck75 wire is reinforcement. The Al 1050 plates were bonded by explosive welding process. The bonding was performed using a Steel Ck75 wire among Al 1050. The plates and wires were explosively welded using parallel system for the investigation (
The measured tensile strength of the Al 1050 plate used was 121 Mpa and Steel Ck75 was 1302 Mpa. The anvil was sand. Anfo was placed in a cardboard box. The detonation was performed by a remote-control system.
The parameters of the EXW were earned from previews two steps (simulation and weldability window). All the EXW tests performed were simulated.
After the EXW, the samples for metallographic observation were cut perpendicular to the detonation direction. The samples have been paid up to 3000 sandpaper and then polished using 3 microns after that samples of the composite set at room temperature for 30 seconds of etching solution according to the following
|
Hf | HNO3 | H2O |
|
1.5 | 3 | 10 |
Two tensile specimens were made to define the mechanical properties of the bonding. The tensile test was carried out according to the
The flyer plate and parent plate are paralleled before the explosion. After the explosion, the flyer plate was bent and impacted obliquely with the parent plate (
At first, the flyer plate was accelerated by a shock wave, resulting from explosion pressure, and then by the spread gaseous products of the explosion. If the stand-off distance was sufficiently large, the flyer plate finally achieved a final velocity (
The collide angle is one of the important parameters of the EXW. The collide angle predicted in the simulations. The collision velocity (Vc) in the Autodyne was gotten by dividing the length of the Al by the total timing of the EXW’s simulation. In this study, the angle velocity (β) and the collision velocity (Vc) were predicted, respectively, at 3479 m·s-1 and 12.1° by AUTODYN.
Numerical simulations were performed to define the appropriate amount of Anfo used in aluminum base composite and the stand-off distance. The stand-off was selected to be about 4 mm. An explosive Rate of R= 6 was found at a suitable rate. Explosive Thickness was 60 mm.
In this paper, all of the parameters are plotted in the weldability window, This diagram is drawn based on the simulation results. It can be plotted in both the collision angle and the collision velocity.
The collision velocity and the collision angle of the simulation are placed in the weldability window (
The term explosive welding has been used to explain the process whereby bonding of wire happens. Explosive bonding happens when two plates collide at an adequate speed to reason doughy flow at the interlayer of connection (
The Al 1050/Steel Ck75/Al 1050 the EXW was fabricated as shown in
a) after cutting and b) after machining
The interface bonding Al 1050/Steel Ck75/Al 1050 was tested by the optical microscope.
Materials | Yield strength (MPa) | Ultimate tensile strength (MPa) |
---|---|---|
Al/Al | 139 | 142.5 |
Al/Steel Ck75/Al | 143 | 154.5 |
The Al/Steel/Al shows the rather improvement in the yield strength and ultimate tensile strength as compared to Al/Al composites. This is possibly due to good interface bonding among Steel and Aluminum. The good interface helps in load transfer from Aluminum to Steel during tensile testing (
Interconnected Steel Ck75 wire reinforced Aluminum base composite was successfully prepared by the explosive welding process. Thus, it seems that the weldability window and the simulation are useful for earing all parameters of explosive welding. The simulation permits voluntary exchange in the parameters without extra cost.
The communication between the numerical simulation and the experiment shows that all parameters are suitable, the stand-off is 4 mm, an explosive Rate of R=6 and the thickness of the explosive is 60 mm.
The aim of the weldability window to predict the welding state before the detonation. Then, using the simulation software, the angle of collision and the impact of velocity were achieved. Subsequently, the help of the weldability window and simulation were determined the exact position of the weld before the explosion and the number of tests reduced.
Thus, it shows that the sample is good to simulate the EXW. The parameters are reasonable to earn from the numerical study.
In this paper which was performed to increase tensile strength, thus, the highest strength was gotten for the reinforced wire composite. Al 1050/Al 1050 sample while the lowest strength was gotten for unreinforced Al 1050/Al 1050 sample. It was observed that the Steel Ck75 wire reinforced composites show maximum improvement in strength among the composite.
The quality of the interface steel wire could improve strength from 142.5 to 154.5 Mpa, and yield strength was increased from 139 to 143 Mpa.
In this study, the weldability window of Al 1050/Al 1050 was plotted. On this basis, Aluminum base composite is reinforced with Steel Ck75 wires by explosive welding. The bonded Al/Steel Ck75/Al by explosive welding was successfully and the bonding didn’t also show any crack or fault.
In conclusion, the weldability criteria and the simulation were successfully considered to predict the suitable welding parameters to catch excellent bonding.
The improvement in tensile properties is strongly dependent on the wire reinforced composites. Tensile tests have shown that the steel wire reinforced Aluminum base composites have satisfactory mechanical properties in that the ultimate tensile strength increases by 8.5% compared to Al/Al.