Posted by LEO440 on May 01, 2010 at 00:01:30:
In Reply to: Re: Re: Inclusions of Al2O3 and MgAl2O4 (spinel) posted by Froilan on February 01, 2010 at 15:06:40:
I see spinel often associated with alumina clusters either as individual or attached particles. In the optical microscope, examine the cluster at higher magnifications for attached and/or 2nd phase particles. It's much easier to determine in the SEM, the spinel particle will contain approximately 17% Mg, but an accurate number depends on making sure the interaction volume is contained within the phase or individual particle. Any scatter into the nearby alumina particle or the surrounding Al metal will greatly reduce any chance of coming up with an accurate number.