The first part of the lesson is to make sure the steel is high-carbon steel, since most other steels aren’t able to be heat treated. It will also have a specific method for its quenching ...

He then hammers the tough, low-carbon steel, which he has shaped so it will make a snug fit into the channel and forges the two metals together. Both types of tamahagane are now exactly where they ...

GRAF: In a very concrete way, we are physically going to remove CO2 emissions by providing better steel. FRAZIER: Scientists have known hydrogen could be used to make steel for decades ...