Japanese HSLA shipbuilding steel development

Cited as the motivation for Tom's mid-1980s Japan trip on behalf of the Navy. Japanese commercial steel mills were producing one-inch plate that required no summer preheat — a millions-of-dollars savings vs. the alloy steels needing 200°F preheat. Sets up the Navy's interest in HSLA for surface ships.

Moisture, of course, is a source of hydrogen. You can tolerate 10 or 20 parts per million hydrogen in these types of steels that have very low preheat. When you go to medium preheat, which I call 100 to 300 degrees Fahrenheit, now you may have a thicker steel, or a higher carbon steel, or a little bit of alloy content — it might be an HSLA steel that's two inches thick. If it was HY80 and it's two or four inches thick you might need three or four hundred degree preheat. If it's HSLA you may only need a hundred to three hundred, or a hundred to two hundred degrees. That's why the Navy wanted to go to HSLA plate steels, and that's one of the reasons they sent me over to Japan in the mid 80s to see how the Japanese were making these steels. The Japanese were making commercial steels for shipbuilding at the time that required no preheat. They might have one-inch-thick plate that in the old days, with an alloy steel, you had to preheat to 200 degrees — now they didn't have to preheat it at all, at least during the summer in Japan. Maybe in the winter they had to get it up there, but they didn't have to preheat it. Saved them millions of dollars in shipbuilding.