Abstract:
The current study is intended to characterise the complex microstructure
that results from autogenous welding of Zr-2.5Nb and its influence on
mechanical properties. Laser beam welding (LBW) and gas tungsten arc
welding (GTAW) were performed on a 1.5 mm thick samples by applying
different combinations of speed and power to vary the heat input. The
effect of cooling rate on β-α phase transformation temperature and the
resulting microstructure was investigated using a Bahr dilatometer. In
addition, mechanical properties were determined by tensile and hardness
testing. The base metal microstructure consisted of a fine structure of Zralpha
with a small fraction of Nb-beta phase. Both LBW- and GTAWwelded
joints displayed similar martensitic microstructures, with the main
difference being the weld geometry and strength.
Description:
This paper
was first presented at the AMI Precious Metals
2017 Conference ‘The Precious Metals
Development Network’ 17–20 October 2017,
Protea Hotel Ranch Resort, Polokwane, South
Africa.
