1) Selection of proper electrodes is a most important factor in order to secure good mechanical properties in arc-welded high manganese steels.
Both 18Cr-8Ni and 16Mn-16Cr electrodes produced the most successful results; the oints welded with use of these electrodes showed the tensile strengths of 40kg/mm
2 and above, with esnsiderable elongation. Other types of electrodes gave poor results; especially the mild steel electrode was found impracticable.
Some improvements of mechanical properties could be expected by water-cooling each pass or welding with straight beads to avoid heat concentration. But arc welding did not particularly injure the mother metal, for the hardness of heat-affected zone was found not so high and the area was much limited.
2) Mn-Ni electrodes were superior to 18-8 and Mn-Cr electrodes for arc-welding high manganese steels and the following chemical content of deposited metal was recommended:
C0.3% Mn 17% Ni 3.5%
3) Gas welding was inapplicable for welding high manganese steels because of very inferior mechanical properties of gas-welded joints as compared with those of arc welding. This is attributed to the existence of harder and remarkably wider heat-affected zones in the case of gas welding.
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