QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY
Online ISSN : 2434-8252
Print ISSN : 0288-4771
Development of 25%Cr SMAW Welding Materials
- Development of High Cr Ferritic Overlay Welding Materials for Recovery Boiler -
Masakazu MATSUIKenji SHINOZAKI
Author information
JOURNAL FREE ACCESS

2016 Volume 34 Issue 3 Pages 175-180

Details
Abstract

In place of the 18%Cr overlay welding material, which has been used for furnace water wall tubes of recovery boilers, a 25%Cr overlay welding material with good corrosion resistance has been newly developed. In consideration of dilution with a carbon steel tube, the Cr content of the new welding materials are designed to be more than 20%Cr. And in order to fine the grains of the weld metal, some elements, such as Nb, Al and Ti, are added to these welding materials.
Mainly two types of welding materials, which have Austenite + Martensite + Ferrite of materials for the three-phase and fully ferritic materials, are examined. As results of weldability tests and bending properties, the fully ferritic welding materials are superior to the three-phase materials, respectively. On the point of the corrosion test, which are exposed into some smelt ashes obtained from the recovery boilers, the corrosion rate of the full ferritic material was confirmed to be the about 1/2 of that of 18%Cr overlay welding material. The 25%Cr overlay welding material was found to exhibit excellent corrosion resistance.
This study introduces the development of 25%Cr ferritic welding material and methods for reliable overlay welding and examines the weldability, the bend property and the corrosion resistance of the 25%Cr overlay welded metal on tube.

Content from these authors
© 2016 by JAPAN WELDING SOCIETY
Previous article Next article
feedback
Top