Study of mechano-chemical machining of ceramics and the effect on thin film behavior. Final technical report 1 May 80-30 Nov 82

Efforts have been made in this program to develop mechanochemical polishing technique for a number of materials and to determine the consequences of mechanochemically polished surfaces on the physical performance of ceramics. The objective of the mechanochemical polishing efforts is to produce scratch-and-damage-free surfaces by finding suitable soft abrasives that remove material from the workpiece through chemical reactions. Mechanochemical polishing effects were observed when hot-pressed and reaction bonded SI3N4 were polished with two oxides of iron, Fe2O3 and Fe3O4. Mechanochemicaly polished surfaces of Si3N4 were analyzed using the techniques of Auger electro spectroscopy, profilometry and interferometry. Data showing the effects of mechanochemical polishing on the strength of hot-pressed Si3N4 and on the adhesion of thin titanium films on this material have been obtained. Also preliminary efforts have been made to find suitable soft abrasives for mechanochemical polishing of GaAs, Spinel (MgO.A12O3) Sic, B4C,and partially stabilized ZrO2.