Effect of M/A Constituents on Mechanical Properties of High Grade Pipeline Steel

Abstract:

The morphological changes, dimension and distribution of M/A constituent in different region of X80 acicular ferrite pipeline steel were investigated; the effect of M/A constituents of X80 on Charpy V-impact and room temperature tensile properties were also discussed by OM and SEM. The results show that: the distribution and morphosis of the M/A constituents have strongly effect on the mechanical properties. The uniformly distributed massive M/A constituents with chord less than 2 μm observed in grains of base metal, presents high impact toughness and high tensile strength, and the strip M/A constituents with chord more than 2 μm observed in welded joint samples exhibits low impact toughness and high tensile strength. It is seems that the changes of the morphosis and distribution of M/A constituents induce the hardening effect during the deformation which is the main reason to the different mechanical property.

• Periodical: Advanced Materials Research (Volumes 284-286)
• Pages: 1271-1274
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.284-286.1271
• Online since: July 2011
• Authors: Li Xia Zhu, Xiao Dong He, Xin Li Han, Ting Ting Qu
• Keywords: Impact Toughness, M/A Constituents, Tension Property, X80 Pipeline Steel

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