The metallurgical department serves as a support for the trouble shooting activities of Techno Fysica.  

We are often consulted in the case of problems related to the dynamical aspects of an installation. Simply put, the majority of our problems regards vibrations, excessive vibrations, but also overload, shock, high inertia forces and such. By performing a failure analysis, an indication is found with regards to the nature of the cause of failure. Based on the results of the failure analysis, a measurement program is composed, aimed at identifying the exact circumstances during which failure is initiated. This makes it possible to "tune" the measurement program to the measurements to be performed, limiting both measurement time as well as costly time for data analysis.

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Additional data will also be recorded, for those rare cases where the measurements do not fully explain the occurrence of a failure, and more thorough analysis is required.

In the case of fatigue, the level of alternating stress at several operating conditions can be exactly established by using strain gages at critical locations. More often than not, it is necessary to combine the results of measurements with a calculation model to extrapolate results from measurements to inaccessible yet critical locations of the part or installation.

Quite often though, a failure analysis is performed as a stand-alone tool, in order to solve puzzles related to the cause of failure, the quality of the materials used, strength, hardness, wear properties and so on. This is usually the case if we perform the failure examinations on behalf of insurance companies, where, oddly enough, only the cause of failure and thus the matter of responsibility is of interest.

Other problems relate to too short life cycle which is often related to wear, heat or corrosion.

Since with too short life cycle, not only a lot of money can be involved, it can have a great influence on safety too. In addition to examination of components which failed prematurely, Techno Fysica also performs condition monitoring programs, during which a vibration "fingerprint" is compared to a reference value. Please follow the link above for more information on our condition monitoring activities.

At Techno Fysica, we apply all kinds of standard mechanical tests in order to establish the material properties of a failed component. These tests are:

•  Hardness
• Tensile strength
• Toughness and ductility                           
• Corrosion resistance                    
• Fracture mechanics·                              
• Strain gauge measurements

In addition, we perform microscopic studies (normal light microscopy and scanning electron microscopy), to look at fracture faces, wear patterns, surface layers, and more. On the basis of interpretation of the results, the cause of the problem is identified.

In most cases, this is enough to implement a modification which completely solves the problem, restoring structural integrity, reliablity and expected operating life times. In other cases, as already mentioned, the outcome of the failure analysis is used as input for a more extensive investigation measurement program, giving direction to the measurements or calculation models.

The failure analysis can also include other disciplines than just examining the related parts. For instance, by modelling the part by means of finite elements, it is possible to evaluate the loading conditions with respect to areas of high stress, and see if the results matches the established failure mechanism. Thus, the effect of both static and dynamic loading can be evaluated, either separately or combined.

This method can be vvery useful, epecially in the case where actual load is estalished by, for instance, strain gauge measurements.