Page 110 - Quick Guide to Welding and Weld Inspection by S.E. Hughes, Clifford Matthews

A Quick Guide to Welding and Weld Inspection

Figure 7.3 Change of joint design

. poor through-thickness ductility due to impurities in the
steel (such as sulphides, sulphur, microinclusions and
small laminations).

The main ways to avoid lamellar tearing occurring are to:
. Change the joint design (Fig. 7.3) to reduce the stress level
across the rolling direction (through the thickness).
Cracking does not occur when contractional stresses are
in the rolling direction. You can relate this to a plank of
wood where the grain is running down the length. If you
apply a load in the grain direction then the wood is very
strong. Apply a load across the grain, however, and the
wood fractures more easily.
. Use a buttering layer around the joint. A buttering layer
(Fig. 7.4) can be applied using a more ductile filler

Figure 7.4 Weld buttering layer

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