Age-hardening behavior of a low-gold dental alloy.
The age-hardening behaviors of a low gold dental alloy were studied by means of differential scanning calorimetry, hardness testing, X-ray diffraction, optical microscopy and transmission election microscopy. Two distinct hardening behaviors were found at two different aging temperatures. Age-hardening at 290 degrees C was attributed to the formation of the metastable AuCuI' ordered phase, and the gradual softening in the overaging stage resulted from the slow growth of this phase. The rapid increase in hardness in the early stage at 495 degrees C was due to the precipitation of the metastable AuCuI' or/and AuCuII' ordered phases, and the rapid decrease in hardness in the overaging stage was a consequence of the growth of these phases and the loss of the coherency strain at the interface between the spindal-like AuCuI platelets and the matrix.
G Pan
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School of Materials Science and Engineering, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, PR of China.
Wang
J N
JN
D002152:Calorimetry, Differential Scanning; D011232:Chemical Precipitation; D003722:Dental Alloys / Q000737:chemistry*; D006047:Gold Alloys / Q000737:chemistry*; D006244:Hardness; D006245:Hardness Tests; D006358:Hot Temperature; D008422:Materials Testing; D008853:Microscopy; D046529:Microscopy, Electron, Transmission; D013997:Time Factors; D014961:X-Ray Diffraction
D003722:Dental Alloys; D006047:Gold Alloys