Papers by Author: Chun Fu Li

Abstract: TWIP steel containing 0.21% C, 24.4% Mn, 0.9% Si, 1.84% Al, 4.61% Cr, 1.89% Ni, 0.41% Mo and 0.012% Nb was investigated. Tensile tests of this steel were performed in the strain rate range of 10−4–10−3 s−1. Results indicate that tensile properties of TWIP steel at room temperature are sensitive to strain rate in the studied range. Analyses on the relationship between strain–hardening exponent and strain rates show that the formation of twins during deformation greatly affects the strain–hardening behavior of TWIP steels.

Abstract: Expandable screen called slotted base pipe functions as skeleton structure in expandable screen. The expansion process is very complicated due to the existence of slots on slotted base pipe and contact friction between expansion tools and tubular. In this work, based on elastic-plastic mechanical analysis of the expandable slotted tube in expansion process, the 3D nonlinear finite element analysis model of contact process was built. Aiming at two specifications of 4-1/2 and 6-5/8 inches 316L stainless steel slotted tubular, expansion deformation process at room temperature with expansion ratios of 25-35% range was simulated. With those works, it hopes to provide a useful foundation for the formulation of expansion technology of expandable screen.

Abstract: There were little works about electrochemical corrosion behaviors that appeared in high H₂S and CO₂ containing environment. In this work, the electrochemical behaviors of tubular steel API-P110 in buffered acidic NaCl solutions saturated with high H₂S and CO₂ containing gases, were investigated by potentiodynamic sweep technique. Analysis of the results shows corrosion density declines with increasing CO₂ content in H₂S/CO₂. The corrosion potential of steel moves towards more negatively with the increase of CO₂ content in H₂S/CO₂. In pH 2.9 solution, Passivity appears in high H₂S and CO₂, but no passivity shows in due to decreasing in high H₂S. In pH 5.3 solution, cathodic liming density comes out and increases with the increasing CO₂ content in H₂S/CO₂, however, no cathodic liming density comes out in H₂S.