Huget E F, de Simon L B, Hertert R S
J Biomed Mater Res. 1978 Jan;12(1):115-21. doi: 10.1002/jbm.820120110.
Short-term stress relaxation of four dental amalgam alloys was studied. Test materials included two conventional lathe-cut restoratives, a spherical alloy, and a dispersed phase product. Specimens were 24-hr-old 4 X 8-mm cylinders. The specimens were compressed and held at constant strain on development of a stress (So) of 28 MN/m2. Subsequent stress relaxation (Dt) was recorded for 60 sec. Data were obtained at eight nominal temperatures between 0 and 55 degrees C. Over the experimental temperature range, fractional stress losses at 60 sec (Dt/So/60) for specimens made from lathe-cut alloys increased from 10% to 58%. The spherical material and the dispersed phase alloy showed fractional stress losses (Dt/So/60) ranging from 9% to 47% and 9% to 31%, respectively. It would appear that particle morphology and alloy composition affect stress-relaxation behavior of dental amalgam. Stress decay patterns enhance significantly the mechanical characterization of amalgam alloys.
研究了四种牙科汞合金的短期应力松弛情况。测试材料包括两种传统的车削切割修复材料、一种球形合金和一种分散相产品。试样为24小时龄期的4×8毫米圆柱体。将试样压缩并在应力（So）为28 MN/m²时保持恒定应变。记录随后60秒内的应力松弛（Dt）情况。在0至55摄氏度之间的八个标称温度下获取数据。在实验温度范围内，由车削切割合金制成的试样在60秒时的分数应力损失（Dt/So/60）从10%增加到58%。球形材料和分散相合金的分数应力损失（Dt/So/60）分别为9%至47%和9%至31%。看来颗粒形态和合金成分会影响牙科汞合金的应力松弛行为。应力衰减模式显著增强了汞合金材料的力学特性。
