Strength and Microstructure of Gallium Alloys

• Published in: Dental Materials Journal Vol. 18; no. 1; pp. 96 - 107
• Main Authors: MILLER, Barbara H., WOLDU, Margaret, NAKAJIMA, Hiroshi, OKABE, Toru
• Format: Journal Article
• Language: English
• Published: Japan The Japanese Society for Dental Materials and Devices 1999
• Subjects: Analysis of Variance; Compressive Strength; Dental Alloys - chemistry; Dental Amalgam; Dental Marginal Adaptation; Dental Restoration, Permanent; Dentistry; Gallium - chemistry; Gallium alloy; Materials Testing; Microscopy, Electron, Scanning; Microstructure; Molecular Structure; Property; Surface Properties; Tensile Strength; Viscosity; X-Ray Diffraction
• ISSN: 0287-4547; 1881-1361
• DOI: 10.4012/dmj.18.96

This study investigated the physical and mechanical properties and the microstructure of four different gallium alloys. For all gallium alloys, the compressive strengths measured at one hour (86-223MPa) and 24 hours (265-286MPa) after specimen preparation were found to be well within the range exhibited by many high-copper amalgams. The creep values and dimensional change of the gallium alloys were comparable to those of leading amalgams, except for the dimensional change value of one alloy. The set gallium alloys consisted of a multi-phase structure including β-Sn, CuGa2, In4Ag9, Ag72Ga28, and Ga5Pd (except for one product that did not contain Pd) that was more complicated than the structure of dental amalgams. Although the gallium alloys had physical and mechanical properties comparable to those of high-copper amalgams, the microstructure, coupled with the instability of the element gallium itself, could make these materials more prone to corrosive attack compared to amalgams.