Comparison of Strength Characteristic of Cast Iron / Mild Steel Welding Joints by Various Welding Process

Abstract

Recently the reduction of the product cost is rapidly advanced, and the demand that must join the cast iron to mild steel is heightening. At present, for the joining of cast iron and mild steel, the mechanical joining using the bolting is usually carried out, and it becomes a cause of the cost increase. If the welding can be applied to the joining of cast iron and mild steel, the contribution to the manufacturing industry will be large.
But when welding engineers consider the welding of these materials, they do not have the appropriate answer for the welding process and the welding consumables.
The welding of cast iron and mild steel is possible. In actuality, the researches on this welding have been carried out. The researches are divided into 2 types. The first is the examination of the weld zone made by changing the filler metal, the flux and the welding wire in same welding process. The second is the examination of the mechanical property and the structure in weld pieces made by one welding process. Therefore the papers in which various welding processes are applied for the material of same condition and then the welding results are examined have not been published yet.
In this study, 11 kinds of test pieces are produced using 4 kinds of generally used welding processes. And in the viewpoint of the practicability, the welding of cast iron and mild steel is examined from hardness, tensile strength, elongation, impact strength, weldability (workability), efficiency and cost.
As the result, that the metal-arc active gas welding using the solid wire for mild steel is suitable for the welding of these materials clarifies.