Grobkörnigem

Grobkörnigem is the German adjective form used to describe a texture or structure composed of relatively large grains or crystals. It is commonly applied across disciplines to indicate that the individual particles or crystals are visible to the naked eye, in contrast to fine-grained materials.

In geology and petrology, grobkörnig refers to rocks and textures with large mineral grains. In igneous rocks, a grobkörnig (phaneritic) texture typically results from slow cooling of magma underground, producing visible crystals such as those in granite or diorite. Metamorphic rocks may likewise display grobkörnige textures when recrystallization yields sizable grains or porphyroblasts. In sedimentology and soil science, grobkörnig describes sediments or soils with large particles, such as gravel or coarse sand, which influence porosity, permeability, and deposition environments.

In materials science and engineering, grobkörnige Mikrostrukturen indicate a large grain size in metals, alloys, or ceramics. Grain size affects mechanical properties: finer grains generally enhance strength and hardness through grain boundary strengthening, while coarser grains can alter toughness and creep resistance and modify diffusion and sintering behavior during processing. Processing steps such as annealing, anneal cooling, or hot working are used to control grain size and achieve desired performance.

The term is encountered in technical descriptions, laboratory notes, and quality classifications, and it is typically paired with a noun in the appropriate case (for example, grobkörniger Sand, grobkörniges Metall). As a descriptive adjective, grobkörnigem conveys the presence of relatively large grains in a material or substrate.