Study on Welding of Low Alloy High Strength Steels (Report 3)

Weldability Tests of Ni-Cr-Mo Steel (1)

Abstract

Following five Testing Methods which were slected out of about twently Weldability Tests being made during past several years, are utilized for Low Alloy High Strength Ni-Cr-Mo Steel on this Study.
Slit Typie Crack Senstivity Test.
C.T.S. Crack Sensitivity Test.
Maximum Hardness Test of Heat Affected Zone.
Single-Bead Bending Test.
V-Notch Charpy impact Test.
Utilized Rolled Steel Plates which have 10, 16 and 37 mm thickness respectively and 50 mm Casted Steel Plates were given by ten Japanese steel manufacturers.
The nature of Coated Electrode NCM-T was reported in the Report (I) and the Report (II) already.
The Result on this Study is suinmerized as follows.
(1) Slit Type Test is quite Effective to resurch the Crack Sensitivity of Low Alloy High Strength Steel.
(2) Serious relation is seen between Crack Sensitivity Ratio in Slit Type Test and Maximum Hardnes in the heat affected zone.
(3) Certain relation is seen between V-Notch Charpy Value and Crack Sensitivity Ratio in Slit Type Test.
(4) Crack Sensitivity Ratio in Single-Bead Bending Test or Slit Type Test has certain relation with the Maximum Hardness in the heat effected zone.
(5) C.T.S. Test can be effective for the Crack Sensitivity Test in the case of austenitic welding of Low Alloy High Strength Steel.