An explanation of processes occurring during production of high-density micro- and nanogranular ceramics without the use of external pressure is proposed on the basis of accumulated published data. It is well known that pore growth commences after the start of transition from open into closed pores, which begins with about 30% open porosity. It is necessary to maintain open pores to the maximum possible total density of sintered ceramics. This may be achieved by slowing down formation of local compaction areas (unequal density of samples) by various methods. Retention of open pores is facilitated by a decrease in shrinkage rate with which there is self-consistent local compaction and less dense surrounding zones. This regime can be implemented in different ways: by reducing the activity of powder particles (powder preliminary heat treatment, and preliminary low-temperature sintering, i.e., presintering), use of additives that slow down shrinkage (preparing transparent ceramics without external pressure), in the molding material preparation stages, workpiece molding, binder removal by adjusting the specimen heating rate (sintering with a controlled shrinkage rate), and prolonged sintering at a relatively low temperature in the second stage of sintering.

中文翻译：

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高密度微米和纳米粒度陶瓷。从开放到封闭的毛孔过渡。第1部分。粉末制备，成型混合物，成型

基于积累的公开数据，提出了在不使用外部压力的情况下生产高密度微米和纳米颗粒陶瓷过程中发生的过程的解释。众所周知，孔的生长开始于从开放的孔向封闭的孔的过渡开始，其开始于约30％的开放孔隙率。有必要将开孔保持到烧结陶瓷的最大可能的总密度。这可以通过使用各种方法减慢局部压实区域（样品密度不均）的形成来实现。收缩率的降低有助于保持开孔，收缩率具有自洽的局部压实作用，周围区域密度较小。可以通过不同方式实施此方案：通过降低粉末颗粒的活性（粉末初步热处理，