kompaktion

Kompaktion is a German term that denotes the densification of a porous material under applied pressure. In geology and sedimentology it describes the diagenetic process by which accumulated sediments become denser as overburden pressure closes pore spaces, potentially leading to lithification. The early stage involves grain rearrangement and expulsion of pore water; later stages may include mineral cementation and plastic deformation of grains.

In materials science, kompaktion refers to powder compaction during forming and sintering. Under external pressure, particles rearrange, deform plastically, and sometimes fracture, producing a higher bulk density and reduced porosity. The efficiency and pathways of kompaktion depend on particle size and shape, moisture content, temperature, applied pressure, and strain rate. It is a central step in the manufacture of ceramics, metals, and composite materials.

Characterization of compaction behavior uses porosity measurements, compression tests, mercury intrusion porosimetry, and imaging methods such as micro-CT to assess pore structure and density evolution. Understanding kompaktion helps predict swelling, permeability changes, mechanical strength, and the onset of cementation or cracking under load.

In related disciplines the concept is often referred to as compaction or densification. Across fields, kompaktion describes how external pressure reorganizes a porous medium into a denser, often stronger solid.