The master sintering curve

The master sintering curve (MSG) has been developed as a means of rapidly predicting the sintering shrinkage and final density of powder compacts based on a small set of preliminary experiments. It has its origins in our quantitative solid state sintering model. The preliminary data can be obtained most readily from 3-5 constant heating rate sintering runs at a variety of heating rates, using dilatometry. Also, isothermal runs may be used. More runs are required without dilatometry. The MSC is derived by plotting the density vs a specific function of temperature and time. The only adjustable parameter is the activation energy, which can be determined with good precision if unknown. Complications arising from surface diffusion and exaggerated grain growth can be detected. Once the MSC has been determined, the sintered shrinkage of similar compacts can be predicted with good precision for arbitrary sintering temperature-time excursions. The concept has been developed and tested for solid state sintering. Its applicability to liquid phase sintering is yet to be determined; it is more likely to be valid with small volume fractions of liquid.