[Aging properties of indium added gold alloys for metal-ceramic system (author's transl)]

Aging properties is studied on Au-10 wt% Pt and Au-10 wt% Pt-0.5 wt% Fe alloys containing 0.2, 0.4 and 2.0 wt% Indium. The results obtained are as follows: 1) In added Au-Pt alloys. From the electrical resistances in the isochronal aging curves, 0.2 and 0.4 wt% Indium added alloys are age-hardenable between 350 degrees and 640 degrees C. Heterogeneous phase in founded in 2.0 wt% Indium added alloy by meanes optical microstructures. This phase is identified fcc Pt3In by meanes X-ray diffraction. 2) In added Au-Pt-Fe alloys 0.2, 0.4 and 2.0 wt% Indium added alloys are age-hardenable between 250 degrees and 620 degrees C. Grain boundary reaction accelerated in 2.0 wt% Indium added alloy, and hardness decreased by overaging. Precipitation of nodule is inhibited in 0.2 wt% Indium added alloy, and aging properties also increase.