A hybrid welding and forging process that joins dissimilar metals in a second has been developed with funding from NASA, which is interested in using the technique for Moon base fabrication.
The Michigan Research Institute, NASA and Michigan-based engineering company Delphi have developed the deformation resistance welding (DRW) process and claim it can produce welds that are stronger than the parent metals.
In DRW, welding electrodes are placed around the area to be welded. The electrodes pulse electricity into the weld area. This brings the metal to be joined almost to melting temperature. Then force is applied rhythmically to deform and merge the mating surfaces.
DRW can join tubes to solids and sheet metal. Unlike conventional welding technologies it does not need a gas environment or consumable. “We have welded cast iron and stainless steel together,” says Delphi’s new venture creation specialist Jayson Pankin. “We’ll have further combination testing and for leak-tight welds. We are working to scale up the process for production.” The process, he claims, will also limit or stop potential causes of galvanic corrosion that could weaken the weld.
ROB COPPINGER / LONDON
Source: Flight International