Yes, when you use Spark-OES (Spark Optical Emission Spectrometry) to analyze an Al-Al2O3 composite, the measured Al content will represent both the aluminum in the metallic matrix and the aluminum oxide (Al2O3) phase.Here's why:

• Spark-OES works by creating a spark that excites the elements present in the sample.
• The excited elements emit light at specific wavelengths, which the instrument detects.
• Based on the detected wavelengths, the instrument quantifies the elemental composition.

However, Spark-OES cannot directly distinguish between different chemical forms of aluminum in the sample. In your case, both the metallic Al and the Al in Al2O3 will contribute to the measured Al signal.

Many thanks, Adbisa :D