Abstract A study of the use of integral preoxidation was conducted on aerospace gear steels. Some aerospace gear manufacturers make use of a preoxidation process that is separate from carburizing to produce parts with uniform case depths and surface hardness. The stand alone preoxidation process adds cost due to additional manufacturing steps, processing time, handling of parts, etc. Integral preoxidation may be a simpler surface activation method to facilitate uniform carburizing. Results and experimental data from the evaluation of X2M test coupons carburized with an integral preoxidation and carburization cycle are presented. The purpose of this document is to highlight pertinent information from the indepth literature review regarding preoxidation of specific aerospace gears steels. A study of the use of integral preoxidation and carburizing processing of X-2M (BMS 7- 223) Steel was conducted and the experimental data is documented and discussed herein.