Effect of zirconium addition on the impact toughness of the heat affected zone in a high strength low alloy pipeline steel

Effect of ZrO2 nanoparticles on the impact properties of shielded metal arc welds

“…Furthermore, nonmetallic inclusions in the nanometer scale can enhance grain refinement by preventing grain growth due to the pinning of grain boundaries [6]. Several studies have reported that ZrO 2 is a very effective nucleation site for the nucleation of acicular ferrite [2][3][4]. The higher magnification SEM micrograph and EDS elemental maps of weld Z3 is shown in Fig.…”

“…It is obvious that the acicular ferrite plates nucleate on the ZrO 2 inclusions. Wang et al [3] and Guo et al [4] have concluded that the ZrO 2 phase is a very effective nucleation site for the nucleation of acicular ferrite, improving the impact toughness. The ZrO 2 inclusions absorb Mn from the steel matrix and deplete Mn from the austenite.…”

“…Acicular ferrite has been known to intragranulary nucleate at non-metallic inclusions in prior austenite grains during the austenite-ferrite transformation [1]. It has been shown that ZrO 2 , among various non-metallic inclusions, is very effective for the nucleation of acicular ferrite [2][3][4]. No research dealing with welds produced by coated electrodes containing ZrO 2 nanoparticles appears in the literature.…”

Grain refinement in the coarse-grained region of the heat-affected zone in low-carbon high-strength microalloyed steels

“…High-strength low-alloy steels, especially those which are bainitic, have been the subject of considerable interest since the last decades [1][2][3][4][5][6][7][8]. They are not only reliable but also have good weldability.…”

“…They are not only reliable but also have good weldability. Therefore, they are often used to fabricate ships, pipe lines and pressure vessels [2,5]. There has recently been a growing trend to apply large heat input welding techniques in increasing the productivity during fabrication.…”