We consider the packings in the plane of discs of radius $1$ and $\sqrt{2}-1$ when the proportions of each type of disc are fixed. The maximal density is determined and the densest packings are described. A phase separation phenomenon appears when there is an excess of small discs.

中文翻译：

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二元圆盘填料的密度：玩转化学计量学

当每种类型的圆盘的比例固定时，我们考虑半径为 $1$ 和 $\sqrt{2}-1$ 的圆盘平面内的填料。确定最大密度并描述最致密的填料。当小圆盘过多时，就会出现相分离现象。