| 摘要 |
A welding electrode has a core of unalloyed or low alloy steel and a coating containing alloying and slag forming ingredients and boron and molybdenum in metallic form such that a deposit formed by the electrode contains 0.0005-0.015% boron and 0.1-1% molybdenum. The coating may also contain iron powder and one or more ingredients capable of binding nitrogen, e.g. aluminium, titanium, zirconium or vanadium or an alloy of one or more of these metals. Weld deposits obtained from such electrodes are .0.2% max..C .0.8% max..Si .2.0% max..Mn .0.1-1.0%.Mo .0.0005-0.15%.B .balance.Fe and impurities An electrode may have a coating comprising: .24.0%.limestone .24.0%.calcium fluoride .5.5%.rutile .3.25%.ferro-silicon .6.75%.silicon-manganese .2.0%.ferro-molybdenum .0.15%.ferro-boron .balance.iron powder together with a small percentage of a nitrogen binding metal, e.g. 0.05% titanium and potassium silicate as a binder. |
