Do not search for "astm e125117a pdf free download" on peer-to-peer networks. These files often contain malware, are scanned incorrectly, or are outdated versions (E1251-04 or E1251-11).
Standard E1251-17a covers aluminum and magnesium. If you are only testing aluminum, this standard is still appropriate. However, specialized magnesium labs sometimes prefer a different standard (like ASTM B954 for magnesium), though E1251-17a is universally accepted. astm e125117a pdf