Summary: MMM technology for ultrasonic stress relief

MMM technology has applications in ultrasonic treatment of high-tech parts, sensitive and complex metal parts, treating of biological implants, surgery and many other fields.


  • Stress relief, Accelerated aging, Extending life-span, Surface treatment
  • Ultrasonic sand blasting
  • Ultrasonic chemical etching,
  • Shor and Ball peening
  • Surface implementation of different particles and powders
  • Ultrasonic quenching and hardening
  • Ultrasonic coating Welds treating Extending fatigue life
  • Accelerated free radicals neutralization
  • Polymerization
  • De-polymerization Degassing and de-bubbling.
  • Improved alloying and casting
  • Production of homogenous biocompatible alloys. Facilitated implantation and/or penetration
  • Deep capillary cleaning applications.

There is much published information about ultrasonic descaling and heat exchangers. MMM structural agitation and descaling works in a similar way, but much faster and more efficiently.

MMM: Multi-frequency, Multimode, Modulated ultrasonic agitation.

MMM agitation is at the same time good for stress relief (evenwithout manual peening).  Of course, manual peening is very efficient and excellent for stress relief, but it takes a long time, and it is not as elegant and comfortable as MMM structural agitation.

MPI's MMM peening is very robust, and much more efficient than similar equipment from competitors.

The combination of an alternating magnetic field and MMM or peening agitation will certainly produce better and faster stress relief and descaling for boilers, pipelines and heat exchangers.

The advantage of MMM-technology applications is that we can use almost the same MMM equipment for heat exchangers preventive maintenance, descaling and continuous in-line cleaning, and for stress relief. Ee only need to apply different settings on MMM ultrasonic generator software.

According to published and experimental work information and experiences, also alternating magnetic field applied on pipelines and heat exchangers is effective both for descaling and stress relief, because a magnetic field produces mechanical vibrations in ferromagnetic bodies, meaning that we can combine acoustic and magnetic agitation.

Applying multiple MMM agitators and enough ultrasonic power, 90% or more of the big ship’s hull or even a complete drilling rig can be destressed in a very clean, quiet, fast and elegant MMM way. No need to peen every weld and joint. For increased security some areas can still be manually treated with the peening tool, but this can be only in a limited number of small areas with special needs.  We can also make complementary combinations with alternating electromagnetic destressing to increase stress relief efficiency in zones with difficult access.

More stress relief literature and presentations on our downloads website.