Weldability of spheroidal graphite cast iron by gas tungsten arc welding

Abstract EN

This research work was carried out to study the weldability of spheroidal graphite cast iron (SGI) by employing the gas tungsten arc welding (GTAW) technique.

The welding electrode used was ENiFe-Cl.

The welding joints were assessed by measuring the tensile strength, hardness and by examination of the microstructure utilizing optical and scanning electron microscope.

Some specimens were preheated to 350oC for 15 min and their results were compared with those of unrepeated specimens.

The weld joints were cooled in air, sand and furnace, thus giving various cooling rates leading to different mechanical properties.

It was concluded that a higher cooling rate produces joints of higher strength and hardness with lower elongation.

Preheating improves the strength and elongation and lowers the hardness.

Quality index improves with preheating.