Niemi L, Herø H
J Dent Res. 1984 Feb;63(2):149-54. doi: 10.1177/00220345840630021101.
The structure of a commercial dental Ag-Pd-Cu-Au casting alloy has been studied by microprobe and X-ray diffraction analyses after various heat treatments. The composition of phases in equilibrium was established. After being annealed at 400 degrees C, 500 degrees C, and 600 degrees C for seven wk, the alloy consisted of three phases: a Cu- and Pd-rich fee phase (alpha 1) with alpha = 0.372nm, a Ag-rich matrix (alpha 2) with alpha = 0.399nm, and an ordered CsCl-type bcc PdCu phase with alpha = 0.296nm. The PdCu phase was not observed above 600 degrees C, and the proportion of the alpha 1 phase decreased sharply above 700 degrees C. After being annealed at 900 degrees C, the alloy matrix was partly decomposed at the Cu-enriched grain boundaries. The decomposed areas grew into the grain interior during subsequent precipitation hardening. No segregation of Au was detected after casting, and the element was evenly distributed throughout the alloy structure after all heat treatments.
通过微探针和X射线衍射分析，研究了一种商用牙科银钯铜金铸造合金在不同热处理后的组织结构。确定了平衡状态下各相的成分。在400℃、500℃和600℃退火7周后，该合金由三相组成：一种富铜和钯的面心立方相（α1），晶格常数α = 0.372nm；一种富银基体（α2），晶格常数α = 0.399nm；以及一种有序的氯化铯型体心立方钯铜相，晶格常数α = 0.296nm。在600℃以上未观察到钯铜相，在700℃以上α1相的比例急剧下降。在900℃退火后，合金基体在富铜的晶界处部分分解。在随后的沉淀硬化过程中，分解区域向晶粒内部扩展。铸造后未检测到金的偏析，经过所有热处理后，该元素在整个合金结构中均匀分布。
