الفهرس 
AcknowledgmentOnly 14 pages are availabe for public view
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Abstract
The object of the present work is to investigate the effect of type of filler metal, welding process and the application of high-nickel buffer layer on the structure and the mechanical
properties of a dissimilar joint composed of austenitic stainless steel on one side and plain carbon steel on the other.To achieve this goal,
carried out.three series of experiments have been In the first series, by applying Shielded Metal Arc Welding process (S~~W), a comparative study between using austenitic and austenitic-ferritic filler metals had been carried out. In the second series, the plain carbon steel side of the joint had been buttered by a high-nickel layer, then welded in
the some manner as in the first series in order to clarify the real advantages of applying this technique.
In the third series, the same joint as above was weld~d using Tungsten Inert Gas process (TIG) in order to compare with the joint produced by SHAW process Test specimens were cut from all the three mentioned series
in order to study tbe macro-and micro-structures, tensile
properties, impact strength and hardness distribution. Ductility
was also studied thro\1gh face, root and side bending tests.Metallographic studies showed that weld metalin adissimilar joint has threo distinct zones ; two diluted zones at
each side of the joint as ~ell as the main weld metal. On that
basis a modified method has been proposed which can predict the composition of the three zones in place of’ the conventional method-whtch pH~dicts an average composition for the whole weld bead.Contrary toexpectations, it has been proven that buttering technique has some drawbacks. Buttering using high-nickel filler
metal reduces both toughness specially at the HAZ on carbon steel side and hardness of the two base metals.
TIG process proved to be superior than SMAW in producing a dissimilc.:L joint a,s it improves toughness and reduces hardness of the we id metal.
Tensile and Bending tests showed that the weakest point with respect to both strength and ductility is the carbon steel base metal.