EFFECT OF TRACE BORON ON IMPACT TOUGHNESS

The effect of trace boron on increasing the impact toughness of high strength weld of σ_b≥850N/mm² Cr-Mn-Si steel was investigated. It was found that trace boron played a definite role in increasing the impact toughness. By dislocation theory, the author made researches on the strengthening mechanism and the distribution and behaviour of trace boron in microstructure.