Additively manufactured particle damping structures: A review of manufacturing and filling approaches, design variables and evidence comparability

Particle damping dissipates vibration energy through relative particle motion, collisions and frictional contacts inside cavities. Additive manufacturing incorporates this mechanism within structural volumes, where retained build powder or added particles can become part of the damping function. Current additively manufactured particle damping (AMPD) literature has moved beyond isolated feasibility demonstrations, but evidence is difficult to transfer because different manufacturing and filling routes, particle state, excitation conditions, baselines and response metrics are discussed under the same label. This review synthesizes a structured table of 108 publication records to map manufacturing and filling approach, validation level, cavity placement and design strategy, frequency ranges, excitation regime, response metrics and reporting completeness. It groups them into 79 independent AMPD evidence units, comprising 64 direct retained-powder and 15 post-filled evidence units. Detailed design, frequency and reporting analyses use the 64 direct evidence units. The synthesis shows that AMPD performance cannot be reduced to cavity volume or a single reported damping value. Instead, it depends on the coupled relation between structural response, powder or particle mobility, cavity placement, internal design, excitation level, baseline choice and response metric. The performance comparison summarizes outcomes in their source metrics across specimen, component and application levels, while showing that direct comparison across evidence units is difficult because key variables are defined, measured and reported differently. Therefore, the review proposes a classification, evidence map and compact reporting set that frame AMPD as a route dependent design problem and support more transferable evaluation of additively manufactured damping concepts for vibration sensitive applications.