Carnegie and Bethlehem Steel were licensed to manufacture Krupp steel plate in 1897
New York Times Nov. 7th, 1897
http://query.nytimes.com/mem/archive-free/pdf?_r=1&res=9A00E5DA123CE433A25754C0A9679D94669ED7CF

Arms and the Man, April 8, 1915, Fred Adolph, “More About Gun Barrel Steel”
https://books.google.com/books?id=EpcwAQAAMAAJ&pg=PA25&lpg
“Krupp makes 200 kinds of steels”