Galvanic corrosion is most common in electrical water heaters and appear on the electrical elements. The axial stress is along the width direction of the plate, which is the only large residual tensile stress in the inner surface that is perpendicular to the thickness of the plate; therefore, it is chosen as a representative stress to study the effects of the pipe size and forming parameters on the stresses after forming Figure 13 is exhibiting the evolution of the stress distributions of the plate after loading, unloading, and moving the plate forward.
By studying the maximum shear stress in the forming process and comparing it with the tested shear strength, the bonding behavior of the bimetallic plate deck pipe in the JCO forming process can be understood. Finally, the influence of the span on the stress of the bimetallic pipe after the forming was studied.
The finite element (FE) method has been widely used in the design and implementation of metal forming to predict the distribution of the stress and strain in the formed part 9 , 10 Kim et al. 11 established a rigid-plastic FE model to predict the edge shape of the initial strip for a thick tube roll forming.
Plate 1 had the strength of the X65 and 2205 plates before the explosive welding, plate 3 had the strength of the X65 and 2205 plate after the explosive welding, and plate 2 had the average strength of the plate before and after the explosive welding, which is summarized in Table 4 The results are shown in Figure 15 It can be observed from Figure 15 the maximum hoop stress and the maximum tensile axial stress on the upper surface increase with increasing plate strength.
With the increase in the span, the maximum tensile axial stress on the upper surface of plate reduces significantly, whereas the hoop stress decreases first and then remains unchanged. Figure 6. The Mises stress contour of the pre-bending after loading. Figure 20. The Mises stress contour of results of the 2D model.
Figure 8 a and bare the Mises stress contours after the J” forming and C” forming, respectively. Another example is the cathodic protection of buried or submerged structures as well as hot water storage tanks In this case, sacrificial anodes work as part of a galvanic couple, promoting corrosion of the anode, while protecting the cathode metal.
The maximum shear stress of the pipe in the JCO forming process is much less than the tested shear strength of the plate. High hardness, contains a lot of alloy hard phase, has good wear resistance and also corrosion resistance, suitable for the application with small impact force and low installation requirements.