Ken Kirby asked 2 questions. Paraphrasing:
It seems to me, that if someone is specifying an element content outside of the normal range, you would ask that person, or organization, to explain the reason for the request, not try to assume a reasoning.
Ken's second question has to do with steelmaking. As all metallurgist know, the chemistry of a steel alloy is made in a batch of liquid. Each batch of liquid steel must be converted into a solid. In modern steelmaking, this conversion is done in a continuous casting machine (caster). Continuous casting has replaced virtually 99% of ingot casting, the previous technology. Gone are the days of ingot-cast un-deoxidized rimmed steel, which accounted for well over 50% of steel produced in North America prior to 1970. All steel solidified in a continuous caster must be deoxidized, and Al is a de-oxidizing element used in most cases (steel for tire-cord wire is one exception). Ken, if you run a check analysis on a sample of the 86B30 you are using, and ask for soluble-Al, I would be surprised if it is less than 0.015%.
ASM International is the world's largest association of materials-centric engineers and scientists. We are dedicated to informing, educating, and connecting the materials community to solve problems and stimulate innovation around the world.
ASM World Headquarters9639 Kinsman RoadMaterials Park, OH 44073-0002
+1 440.462.0292 (International)