ジルコニウムおよびジルカロイ : 2 合金の点溶接に関する研究

概要

論文の詳細を見る
In this report optimum spot welding conditions, mechanical and corrosive properties of welded joints for pure Zirconium (Zr) and Zircaloy-2 (Zr-2) were investigated and the following conclusions were obtained : (1) It is recommended to pickle (HF 5%+HNO_3 45%+H_2O 50%) the specimen prior to spot welding. (2) Optimum spot welding conditions for various thicknesses of specimens are given approximately by the following equations Welding current=5,000+5,000T_0 (A) Electrode force=80+220T_0(kg) Weld time=1+5T_0 (cycle) where T_0 : Thickness of specimen in mm (3) No welding defect in nugget such as crack or porosity was detected (4) Welded joints made by optimumwelding conditions had the following mechanical properties : (i) Fracture by tension-shear test occured at the bond of base metal and heat affected zone and showed button-like fracture. (ii) The thicker the thickness, the stronger the strength by tension-shear test. The joint of Zr-2 was generally stronger than Zr. (iii) Nugget of a spot weld was harder than weld metal of a TIG weld, because cooling rate in the former was faster than the latter. (iv) Nugget showed many dendrites in macrostructure and α' (acicular α) phase in microstructure in each dendrite. (5) The holding time at temperatures over 400 or 500℃ of specimen surface which contacted with air was less than 10 cycles and, accordingly, the deleterious reaction air seems to be negligible. (6) Corrosion resistance of spot weld in high temperature high pressure (320℃, 115-117 atm) test was good whether pickled or not pickled after welding. Therefore, the corrosion resistance of spot weld in considered to be satisfactory even if used in a nuclear reactor.
1961-06-25

ジルコニウムおよびジルカロイ : 2 合金の点溶接に関する研究

スポンサーリンク

概要

著者

関連論文

スポンサーリンク