抄録
Using slit type specimens, crack tests were performed to evaluate the cracking tendency of structural high tensile Mn-Si steels.
It was found that as the maximum hardness in heat-affected zone (Hmax.) increased the cracking tendency of weld became marked. Cracks usually originated from the root of weld and grew along the heat-affected zone, then turning into the deposit. Hmax. seemed to increase proportionally with C and Mn contents but hardly increased with Si content for the range investigated. To prevent the weld crack C should be kept as low as possible; Mn below about 1.2%. There was not any indication that Si content promoted the craking tendency of weld. Of various types of electrodes applied for the test, the low hydrogen type proved to possess sufficient anti-cracking property.
