TWI Industrial Member Report Summary 185/1982
By M L E Davis and N Bailey
Background
The effects of adding the deoxidants, ferro-titanium and calcium disilicide, and the mineral rutile to types of flux used for high strength steel are considered with particular regard to element transfer behaviour.
Incomplete welds were prepared, consisting of two passes, a root run in the 2/3 side of a 1/3-2/3 prepared plate and a penetration pass filling the 1/3 section, the latter being used for all principal measurements. The welds were made on aluminium-treated plate using 1%Mn wire and an alumina basic flux or a 1.5%Mn wire and a basic flux.
The deoxidant additions did little to reduce weld oxygen contents. Additions of 4% and 8% by weight ferro-titanium reduced weld oxygen contents with the alumina basic flux but not with the basic flux which, even without any deoxidants, gave very low weld oxygen levels. These additions, however, increased the transfer of titanium, with both flux types and also increased the transfer of silicon and manganese to the weld metal with the alumina basic flux and decreased the loss from the weld metal of them when using the basic flux. Additions of 4% rutile transferred small amounts of titanium to the weld metal but did not influence the transfer of other elements.
The additions of calcium disilicide had no apparent effect on the weld oxygen contents or, on the levels of other elements, although the silicon content was increased more particularly for welds made using the basic flux.