At least one transducer of an apparatus in one example is configured to generate a first standing wave field within a cavity. The first standing wave field exerts a first field-induced force to cause a plurality of particles within the cavity to align in a desired configuration. The at least one transducer is configured to generate a second standing wave field within the cavity. The second standing wave field causes one or more of the plurality of particles within the cavity to fuse into the desired configuration.