【摘要】 本文首次提出了该焊缝的拘束与韧性之间的关系问题。为此作者设计了三种不同拘束状态的实际焊接接头,即全拘束(Ⅰ)、半拘束(Ⅱ)及无拘束(Ⅲ).对用OOCr13Ni6MOTi焊丝和TIG(或MIG)完成的多层焊缝进行了研究。在该条件下,当焊缝由高温冷却时,在γ→α相变之前的奥氏体温度区,不可避免地存在着一定的拘束应变,该应变协助马氏体相变,导致在形态上马氏体单元体和板条宽度都减小,从而在力学性能方面大大提高了焊缝的冲击韧性。实验结果证明,该韧性随着拘束应变的增加而增大,例如拘束状态Ⅰ的冲击韧性比拘束状态Ⅲ的提高了40％。更多还原

【Abstract】 This paper puts forward the problem of the relationship between restraint and impact toughness in the weld metals. Three kinds of restraint conditions were designed,i.e.complete restraint(Ⅰ),semi-restraint(Ⅱ)and restraint free(Ⅲ)for specimens with multilayer weld metals finished by using OOCr13Ni6MoTi welding wire and TIG(or MIG)technique. After welding,there inevitably is certain restraint of strain in austenitic temperature range of weld metals.This strain helps martensitic transformation and results in a decreas of the sizes of martensitic laths,and thus significantly increases the impact toughness of weld metals.Experimental results indicate that the toughness increases with increasing restraint strain,for example,the impact toughness of condition(Ⅰ)is higher than that of condition(Ⅲ).更多还原