NUCLEATION AND GROWTH OF INTRAGRANULAR ACICULAR FERRITE AND ITS EFFECT ON GRAIN REFINEMENT OF THE HEAT-AFFECTED-ZONE

作者：Shu Wei; Wang Xuemin^*; Li Shurui; He Xinlai

来源：Acta Metallurgica Sinica, 2011, 47(4): 435-441.

DOI：10.3724/SP.J.1037.2010.00578

• heat-affected-zone (HAZ)
• intragranular acicular ferrite (IAF)
• TiO(x)-MnS complex inclusion
• Mn-depleted zone
• grain refinement

Nucleation and growth of intragranular acicular ferrites (IAFs) in heat-affected-zone (HAZ) have been investigated by the observation of microstructures quenched at different temperatures during the cooling process of welding thermal cycle. :It is proved that IAFs can divide the prior austenite grains and refine the intragranular microstructures. AES show that there is a Mn-depleted-zone near the interface of TiO(x)-MnS complex inclusion. IAFs prefer to nucleate on the complex inclusion, and a single inclusion can usually induce several IAFs to nucleate. IAFs grow up with lowering of the temperature during the cooling process. Quenched martensite and bainite could collide with the IAFs and make them deform, but the quenched martensite and bainite can not penetrate through the IAFs. IAFs divide the prior austenite grain and restrain the growth of other intragranular microstructures, and therefore HAZ's microstructure is finally refined effectively.

• 出版日期2011-4
• 单位北京科技大学