Effect of M/A Constituents on Mechanical Properties of High Grade Pipeline Steel
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.
Xiaoming Sang, Pengcheng Wang, Liqun Ai, Yungang Li and Jinglong Bu
L. X. Zhu et al., "Effect of M/A Constituents on Mechanical Properties of High Grade Pipeline Steel", Advanced Materials Research, Vols. 284-286, pp. 1271-1274, 2011