Influence on martensite‐start‐temperature and volume expansion of low‐transformation‐temperature materials used for residual stress relief in beam welding

Low‐transformation‐temperature materials (LTT) are used as high‐alloy welding filler material for high‐strength steels in order to minimize the tensile stresses and resulting distortion of the component during the welding process. The increase in the volume of the structure produced during martensitic transformation is utilized in order to counteract the volume shrinkage due to the cooling process. As stated in the field of study various elements influence the starting temperature of the martensite transformation, the influence on the volume expansion during the martensite formation is unknown. The influence of alloying elements nickel and chromium on the conversion behavior of low‐transformation‐temperature materials is to be investigated in detail. In particular, the effect of the variation of the mentioned elements on the starting temperature of the martensitic phase transformation and the extent of the volume expansion associated with that is investigated. In addition, the change in the hardness of the different low‐transformation‐temperature alloys is recorded and compared.

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