A method of manufacturing the electron beam welding for steel and electron beam welded joints

摘要

0.02% ~0.10%, Si:: C by mass% 0.03% ~0.30%, Mn: 1.5% ~2.5%, Ti: 0.005% ~0.015% , N: 0.0020% ~0.0060%, O: 0.0010% ~0.0035%, Mg: 0.0003% ~0.0027%, Ca: the 0.0027%, 0.0003% It contains at least, Al: 0.015% or less, P: 0.015% or less, S: to each limited to 0.010% or less, and inevitable impurities balance iron, 0.0006% ≦ Mg + Ca ≦ 0. satisfied the 0040%, the index value is CeEBB a 0.65% 0.42%, in the center of plate thickness of the cross-section along the thickness direction of the steel, the equivalent circle diameter of 1.0μm or more oxidation 20 The number is / mm ^{2 or} less, in the plate thickness center, circle equivalent diameter containing more than 7% of Mg is 1 × ¹⁰ 3 ~1 × ^{10 5} is the number of oxidation less than 0.5μm 0.05μm more electron beam welding for steel is a number / mm ^2.