Physical Investigations on the Nitrogen in the Weld Metal (1st Report)

Abstract

Nowadays it is said that nitrogen in the weld metal will be the most probable causes of the bluebrittleness and temper-brittleness of the weld metal. The authors examined the relations among hardness, lattice. intervals, nitrogen and oxygen contents to determine the behavior of nitrogen and oxygen in the phenomenon of aging. As a result of these preliminary testings was noted that :
1) Hardnesses and lattice intervals are both approximately proportional to the nitrogen and oxygen contents of the weld metal when it has been made under the constant conditions of welding.
2) The phenomena of precipitation and remelting of nitrogen can be recognized in the variations of hardnesses and lattice-intervals.