二相ステンレス鋼中のσ相,炭化物,窒化物の態別定量法及び析出挙動
1989 年 75 巻 10 号 p. 1936-1942
詳細
1989 年 75 巻 10 号 p. 1936-1942
A method for quantitative analysis of σ-phase, carbides and nitrides in duplex stainless steel was investigated and the analytical procedure has been established. And then, precipitation behavior of the σ-phase in duplex stainless steel was investigated by using this method.
The results obtained are summarized as follows :
(1) The residues adhered to the sample surface after potentiostatic electrolysis in 1%HCl-10% acetylacetone-methanol electrolyte (1%HA) can not be teared off by only ultrasonic cleaning, and in this case, the residues can be teared off by polishing the sample surface with a wire brush.
(2) Only the σ-phase in the above mentioned precipitates is gradually dissolved by 10%Br2-methanol dissolution treatment, and consequently the composition of the σ-phase can be analyzed by using this solution.
(3) The precipitates except the σ-phase are quantitatively extracted by galvanostatic electrolysis in 10% tetramethyl ammoniumchloride-10% acetylacetone-methanol electrolyte (10%TMAC), and the amount and composition of carbides and nitrides can be analyzed.
(4) The amount and composition of the σ-phase, carbides and nitrides can be analyzed by using the procedures from (1) to (3) and previous report.
(5) The formation of the σ-phase is very fast at 1 073 K, and the amount of the σ-phase is quite larger than that of carbides and nitrides.
