Strain aging behaviour of Cu-containing microalloyed low carbon seamless pipeline steel

Abstract

The effect of strain aging on the microstructure, including copper precipitation, and mechanical properties of an industrially produced Cu-containing microalloyed low carbon pipeline steel has been investigated. The precipitation of round bcc-Cu particles with diameters of ∼7 nm has been clearly observed in the microstructure after strain aging. The strength of pipeline steel significantly increased while the elongation and impact toughness did not apparently decrease. Unlike welded pipe, few carbon atoms in supersaturated solid solution diffuse to the mobile dislocations, forming Cottrell atmospheres and producing strain aging phenomenon in seamless pipe. This difference is attributed to the different pipe making technique: thermo mechanically controlled processed for welded pipe and traditional heat-treatment for seamless pipe.

Mechanical Characterization of Resistance-Welded and Seamless API 5L X52 Pipes: A Comparative Study

“…Hasenhutl et al [37] studied ductile fracture resistance and fracture toughness using the Charpy impact of a seamless pipe. Scherf et al [38] presented a study that developed an innovative low-carbon concept for X100 seamless pipes in low-temperature applications, obtaining excellent CVN impact behavior below −60 • C. Also, some works have been conducted on the strain of seamless pipeline steel [39], heat treatments [40,41], and the application of microalloyed steel [42]. Another important characteristic of pipeline steel is the anisotropy of its mechanical properties, strength, and toughness [30].…”

Feasibility of studying 460 MPa high-strength steel affected by strain aging with acoustic emission method

“…Mild steel materials are widely employed in many building structures, engineering machinery and infrastructure. Presently, mechanical property tests are common and mature methods to evaluate the effects of strain aging on steel materials, including the Charpy impact test, Vickers hardness test, tensile test and fracture toughness test (Chemingui et al, 2010; Que et al, 2019; Ule et al, 1996; Wu et al, 2017; Zhao et al, 2012). The above conventional tests have limitations in evaluating an in-service structure affected by strain aging because sampling is required for these destructive tests.…”

“…The results indicated that the ductility of the material decreased significantly owing to the strain aging effect, such that the additional displacement and bearing capacity (P) of the steel beam correspondingly decreased. Recently, the effect of strain aging on steel materials has been considered in various fields, such as pipeline steel (Wu et al, 2017), reactor pressure vessel steel (Que et al, 2019), reinforcing rebars (Loporcaro et al, 2019) and steel panels for automotive applications (Yuan et al, 2018). However, the effect of static strain aging on partially damaged steel in building structures has not been investigated extensively.…”

Corrosion Resistance of Cu-modified 3Cr Low-alloy Steel in 3.5%NaCl Solution

“…[3][4][5] At present, ocean oil exploitation is becoming more and more important as oil requirement is rapidly increasing and reserves in land are reducing. 6,7) 3Cr steel will be widely used as construction materials in ocean oil exploitation because of good performance in terms of both cost and CO 2 corrosion resistance. It is well known that approximately 20% of the total corrosion cost in marine industry is due to Microbially Influence Corrosion (MIC).…”