Several physical processes can conspire to generate avalanches in materials. Such processes include avalanche mechanisms like dislocation movements, friction processes by pinning magnetic domain walls, moving dislocation tangles, hole collapse in porous materials, collisions of ferroelectric and ferroelastic domain boundaries, kinks in interfaces, and many more. Known methods to distinguish between these species which allow the physical identification of multiavalanche processes are reviewed. A new approach where the scaling relationship between the avalanche energies E and amplitudes A is considered is then described. Avalanches with single mechanisms scale experimentally as E = SiAi2. The energy E reflects the duration D of the avalanche and A(t), the temporal amplitude. The scaling prefactor S depends explicitly on the duration of the avalanche and on details of the avalanche profiles. It is reported that S is not a universal constant but assumes different values depending on the avalanche mechanism. If avalanches coincide, they can still show multivalued scaling between E and A with different S‐values for each branch. Examples for this multibranching effect in low‐Ni 316L stainless steel, 316L stainless steel, polycrystalline Ni, TC21 titanium alloy, and a Fe40Mn40Co10Cr10 high‐entropy alloy are shown.

External electric or magnetic fields, and mechanical stresses generate microstructures in materials which are key to many applications. The creation of these microstructures progresses via avalanches where local changes trigger other changes nearby, until one full avalanche has exhausted itself and the next avalanche starts. In article number http://doi.wiley.com/10.1002/pssb.202100465, Xiangdong Ding, Ekhard K.H. Salje and co‐workers show that in sufficiently complex materials several physical processes can conspire to generate simultaneously different types of avalanches (e.g., dislocation nucleation and growth + martensitic transformation, dislocation nucleation and growth + twinning/detwinning, and dislocation nucleation and growth + dislocation entanglement). They are distinct by their ‘multibranching’ of the energy dispersion which is identified as a new design criterium to tailored materials with emerging properties.

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