Applicability of Nonaqueous Electrolytes for Electrolytic Extraction of Inclusion Particles Containing Zr, Ti, and Ce

Abstract

The estimation of fine inclusion particles is required in order to clarify its effect on the miniaturization of steel grain. In this study, the stability of ZrO2, Ti2O3, TiAl2O5, Ce2O3, and CeS particles during extraction was examined using acid, halogen-methanol, and nonaqueous electrolytes. ZrO2, Ti2O3, and TiAl2O5 particles hardly dissolved in 4%MS (4 v/v% methylsalicylate-1 w/v% tetramethylammonium chloride-methanol) and 10%AA (10 v/v% acetylacetones-1 w/v% tetramethylammonium chloride-methanol) electrolytes, while Ce2O3 and CeS particles did not dissolve in a 2%TEA-Ba (2 v/v% triethanolamine-1 w/v% tetramethylammonium chloride-methanol containing 0.16-0.24 w/v% Ba) electrolyte during potentiostatic extraction. The O content of the extracted ZrO2, Ti2O3, and Ce2O3 inclusion particles agreed approximately with the difference between analyzed total O content and calculated equilibrium O content of the metal, and the S content of the extracted CeS inclusion particles agreed with the analyzed total S content of the metal. The Ce content of the extracted inclusion particles was in agreement with that calculated using the results of two-dimensional measurements.

Effect of the Ti, Al Contents on the Inclusion Characteristics in Steels with TiO2 and TiN Particle Additions

“…[15][16][17][18] The sample was extracted using a potentiometric electrolytic extraction technique (4 V and 50 mA) so that the total amount of the www.steel-research.de charge reached 500 Coulomb for a 10% acetylaceton electrolyte (AA) solution. The selection of the electrolyte was done based on previously successful studies of Ti 2 O 3 and Al 2 TiO 5 particles by Inoue et al [19] The amount of dissolved metal was about 0.12 g. The electrolyte solution was filtered by using a polycarbonate (PC) membrane filter with an open pore size of 0.05 mm (47 mm in diameter). Thereafter, the particles on a film filter were measured by using Scanning Electron Microscopy (SEM).…”

Evaluation of Sulfide Inclusions before and after Deformation of Steel by Using the Electrolytic Extraction Method

“…), carbides, sulfides, multicomponent inclusions, etc. have successfully been studied by using nonaqueous electrolytes in the EE method [10,14,15]. In this study, a soft 10%AA electrolyte was used for electrolytic extraction of all steel samples.…”

“…Therefore, the three-dimensional electrolytic extraction (3D EE) method has been judged to be more accurate than the 2D CS method to determine the real size of the inclusion [7,8]. Previously several studies [6][7][8][9][10] have presented a comparison of different investigation methods. Overall, the results show that to determine the regular sizes and morphologies of elongated inclusions, the 3D extraction method should be applied to acquire realistic results.…”

Three-dimensional Investigations of Non-metallic Inclusions in Stainless Steels before and after Machining

“…Compared to the extraction methods by using acid and neutral aqueous electrolytes, the use of nonaqueous electrolytes shows its good reproducibility, especially with respect to dissolution loss of chemically unstable inclusions, when a suitable nonaqueous electrolyte for specific inclusion phases is selected. [21][22][23] Moreover, it was reported 22) that the 10%AA electrolyte can be successfully used for extraction of complex non-metallic inclusions contained Al 2 O 3 , SiO 2 , CaO, MgO, TiO x , MnS, and CaS without dissolution loss of inclusion components during extractions. During the electrolytic dissolution of the steel matrix, more stable nonmetallic inclusions can be extracted from steel.…”