Specific Joining Applications for Tubular Components
A Methods for integration of AHSS tubular components into a stamped steel structure.
While considering joining of tubular components one should consider tube as a steel sheet, which has a shape of closed cross-section. Two things distinguish the tube from the original sheet material
a. the work hardening, which takes place during the tube manufacturing process, as discussed in clause “3.8 Tube forming”.
b. the weld seam, which means an area of non-uniformity in the tubular cross section. Chemical analysis, microstructure and strength of the steel are the main factors influencing the weldability and weld properties, as discussed in clause 4.
In case of structural welds the periphery of the welded joint is normally decisive and inmost applications the possible influence of the tube weld seam can be ingnored. Therefore the first approach is, that tubular components ma de of AHSS’s can be joined using same techniques, which
a. are normally used in similar applications when using conventional or HSLA steels
b. and recommended for the actual AHSS material, which is used for tube manufacturing,
For example in case of DP steels the steel manufacturer often confirms, that their DP steels are weldable with same conventional welding techniques as those employed for mild steels. When this is the case, the approach is in using those techniques normally in this kind of applications.
Sometimes, as a result of redesign and wall thinning, there may arise needs
a. for improved accuracy of positioning the components prior to welding
b. to adjust the welding parameters to match the reduced wall thickness and the reduced stiffness of the welded surfaces