| Abstract: |
Instead of conventional EB single-pool welding of cast iron welds, a multi-pool welding tech-nique, i.e. simultaneous processing of the EB in several pools, was carried out and investi-gated. Porosity and hardness of the welding seam could be reduced considerably. However it was not possible to avoid cold cracks completely. For this reason, a multi-process technology with multi-pool welding and local thermal treatment of the welds and the HAZ with the help of EB thermal fields was created.
Within the present work the current results concerning process integrated preheating and/or postheating by EB thermal fields used for EB welding of different cast irons (GJV-300, GJL-250, GJS-400, ADI) will be discussed. The results were characterised by visual methods, microstructural investigations, hardness measurements, tension tests and static fracture me-chanic tests. With the help of thermal EB preheating fields, hardness is reduced in the welding seam and flawless - in particular crack free - welds are produced. The application of addi-tional postheating fields reduces hardness in the HAZ by defined local tempering processes.
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