For the welding of titanium-steel clad plates, how to effectively inhibit the alloying reaction of the titanium cladding and the steel base during the welding process, thereby reducing the formation of brittle Ti-Fe intermetallic compounds, and reducing or even avoiding the dilution of the titanium cladding. Occurrence is the key to realizing its high-strength and reliable connection, and it is also the focus of domestic and foreign experts and scholars. At present, one of the main methods is to use different groove designs to avoid direct contact between titanium and steel by layered welding; another commonly used method is to add a transition layer during welding to prevent titanium from being exposed to high temperatures. In addition, some scholars have tried to use the laser one-time penetration method to carry out efficient welding of titanium-steel clad plates in order to improve the efficiency of clad plate welding.
1. Design of groove form Through the design of different groove structures, combined with the method of layered welding, the direct contact between the molten steel base layer and the titanium cladding during the welding process can be avoided, thereby reducing the brittle Ti-Fe intermetallic compound in the joint. generated purpose.
Among them, a common treatment method is to remove the titanium cladding in the area to be welded before welding, then only weld the remaining steel substrate, then add a compensation plate on the side of the titanium cladding, and finally carry out the compensation plate and the titanium cladding. The welding between layers. Because the titanium cladding in contact with the steel base layer is removed before welding, the contact between the molten steel base layer and the titanium cladding is avoided during welding, thereby avoiding the formation of intermetallic compounds. However, it is worth noting that under this welding method, it is still difficult to achieve an effective metallurgical bond between the titanium filler and the steel base, which will affect the reliability of the joint during service to a certain extent.
2. Through multi-layer and multi-pass welding, as well as layered welding + transition layer, penetration welding can reduce the number of intermetallic compounds in the joint and improve performance. Research has also confirmed that reducing welding heat input can reduce the number of intermetallic compounds. The amount of compound will play a positive role. Compared with the traditional arc welding method, high-energy beam welding has a good application potential in the welding of titanium-steel clad plates due to its significant advantages of high energy density and low welding heat input. The research on beam welding is still in its infancy.
Preliminary research results show that the penetration welding of composite plates can effectively improve the welding efficiency compared with the multi-layer multi-pass welding technology by utilizing the characteristics of high energy density, low heat input, and strong controllability of the high-energy beam heat source. At the same time, the quality of welded joints can be further improved by adding interlayer metal. However, at present, the welding of composite plates by high-energy beam welding technology, including the selection of transition layer metal types and the addition method, still needs to be systematically and deeply studied.
At present, the research and engineering application of titanium-steel clad plate welding by combining multi-pass welding technology with the addition of a transition layer has been relatively mature. However, the multi-layer multi-pass welding process has the disadvantages of a cumbersome process and low efficiency, which limits its wider application to a certain extent. Although high-energy beam welding technologies such as lasers and electron beams have the characteristics of high energy density and low heat input, the one-time penetration welding of composite boards has shown good potential in improving the welding efficiency of composite boards. However, in the fields of how to select, design and add transition layer metals to further improve the quality of joints, there is still an urgent need for in-depth and systematic research, which will also be one of the key development directions in this field in the future. In addition, some emerging welding technologies, such as solid-phase friction stir welding technology, can effectively reduce the formation of brittle intermetallic compounds during the welding of clad plates because of their significant advantages of low welding heat input. This technology is currently used in aluminum The welding field of copper-clad plates has been initially applied, and good results have been obtained. Since the clad plate has certain similarities in structure and welding characteristics, it also has certain application prospects in the field of welding titanium steel clad plates. Therefore, how to promote the application of some new welding technologies in the field of titanium-steel clad plate welding, so as to further improve its welding efficiency and quality, will also be one of the important directions for the future development of this field.
