Master Sintering Curve: A Practical Approach to Sintering

TLDR

Sintering geometry often depends solely on density when a single diffusion mechanism dominates, motivating the master sintering curve concept that describes behavior independent of heating profiles. The study aims to predict densification outcomes across varied thermal histories by formulating and constructing a master sintering curve. The authors develop the curve using a model alumina sintering experiment and analytical construction to illustrate the concept. Master sintering curves for ZnO, nickel, and alumina variants show that densification can be predicted for arbitrary temperature–time paths with few experiments, and deviations from single‑mechanism assumptions are readily detected.

Abstract

One of the ultimate objectives for sintering studies is to be able to predict densiflcation results under different thermal histories for a given processing method. It has been reported that the geometric parameters related to sintering often are functions only of density for a given powder and green‐body process, provided that one diffusion mechanism dominates in the sintering process. Based on this report, the concept of a master sintering curve has been developed that characterizes the sintering behavior for a given powder and green‐body process regardless of the heating profiles. The formulation and construction of the master sintering curve are given in this paper. A model experiment on sintering of alumina is used and analyzed to demonstrate this new concept. Examples of the master sintering curves obtained from other powder systems (ZnO, nickel, A1 2 O 3 (5 vol% TiO 2 ), and A1 2 O 3 (5 vol% ZrO 2 )) are presented. When this new method is used, densification behavior can be predicted under arbitrary temperature‐time excursions following a minimal set of preliminary experiments, and these predictions can be used in planning sintering strategies. Moreover, deviations from the assumption of a single mechanism can be observed readily.