. Transactions. ntal AUoys 694 Copper Amalgam 694 PRACTICAL APPLICATIONS OF THE RESLTLTS 695 Phenomena which reveal chemical and physical processes that prob-ably go on in manj alloys at temperatures not far removed from theirmelting ranges are observable in dental amalgams. These amalgamsshould, therefore, be of even more interest to the metallographer, themetallurgist, the chemist, and the physicist than to the dentist whouses them for saving decaying teeth. For this reason I am here de- * Director, Department of Physical Research, The L. D. Caulk Co. VOL. uc.—42. 658 METALLOGRAPHIC PHENOMEN
. Transactions. ntal AUoys 694 Copper Amalgam 694 PRACTICAL APPLICATIONS OF THE RESLTLTS 695 Phenomena which reveal chemical and physical processes that prob-ably go on in manj alloys at temperatures not far removed from theirmelting ranges are observable in dental amalgams. These amalgamsshould, therefore, be of even more interest to the metallographer, themetallurgist, the chemist, and the physicist than to the dentist whouses them for saving decaying teeth. For this reason I am here de- * Director, Department of Physical Research, The L. D. Caulk Co. VOL. uc.—42. 658 METALLOGRAPHIC PHENOMENA OBSERVED IX AMALGAMS scribing a few of the results recently obtained during the course of asystematic investigation of dental alloys. ^ In order to keep this account within reasonable bounds, I shall confinemyself almost entireh to the consideration of strength in compression(crushing strength) and of dimensional changes during hardening (reac-tion expansion). Conditions influencing the mercury content^ will. Fig. 1.^Spring dyxamometer devised by Dr. Black for testing crushingstrength and flow of dental filling materials. receive some attention. A few results have already been communicatedto the American Phj-sical Society.^ In this investigation I was assisted by Paris T. Carlisle, 4th, and by Miss MarthaC. Borton. To both of these I am greatly indebted for the care with which theylooked after the numerous experimental details and records of some thousands oftests, the routine measurements for wliioh were made, as a rule, by 3oung women whowere trained specially for the duties assigned to them. - This term is here used to mean the per cent, of mercurj-in an amalgam. Seep. 662. ^A. W. Gray and P. T. Carlisle: The Influence of Temperature upon the CrushingStrength of a Dental Amalgam. Rochester Meeting. Physical Review (1918) 11,194. The Influence of the Pressure and the Time Employed in Condensing a DentalAmalgam upon its Crushing Strength at Temperatures between 10° and 10
Size: 1500px × 1665px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bo, bookcentury1800, bookdecade1870, booksubjectmineralindustries
