Fatigue Failure Investigative Services

We know fatigue failure is no joking matter - lives and companies reputations are potentially at risk every time a product fails. Discovering the reason for a fatigue failure is an engineering detective activity that needs highly honed expert skills to solve!

Our experts use a wide range of analysis and modeling tools including fatigue crack initiation, fracture mechanics (LEFM, EPFM) thermal mechanical fatigue and creep fatigue analyses. A wide range of specialist tools are required to model and understand the mechanisms and drivers that caused a failure often when the information available is sketchy.

Fatigue-Expert has a strong background in this kind of work based on many different failure investigations. We have worked on a wide range of applications such as rail rolling stock, power plant, vehicle chassis, vehicle body, aerospace components, wind turbines and general production machinery.

For confidentiality reasons, details cannot be presented here, but you are invited to contact us for a confidential discussion about your company's specific needs. 

Fatigue testing can take a long time and if products fail close to but before the required sign off period has been achieved, then repeat testing almost doubles the time required to achieve sign-off.

In addition, products facing use in new markets could require further sign-off testing to ensure they perform as required and maintain their reputation. Again this is time consuming and requires special consideration when planning tests.

Fatigue-Expert can help your team with methods and technology to design optimum fatigue tests where the maximum information is obtained from the minimum amount of testing. Accelerating fatigue tests is a specialist subject since increasing the frequency of the loading is dangerous as it can change the model of failure and test life. In this case, the results can't be applied to the product design process.

Again our fatigue expert will work closely with your engineers to understand your product operational performance envelope, design and materials. From this information a baseline analysis will be performed to model the fatigue performance. Using these results, test optimisation can be carried out and applied to the next test series.

Good fatigue design is not something that can be added on easily or cheaply in the later stages of a product's design and development journey. It should be part of the up front concept design process which typically considers a range of variables that will impact fatigue performance.

Here are some of the ways we can support your product design process:

Independent assessment of fatigue critical features to ensure that as the design matures any modifications do not increase fatigue failure risk and reduce fatigue strength.

Sizing & layout studies focusing on fatigue inputs such as inertial loads, sources of dynamic load, load paths, static load, loads arising from shipping the product and installation loads to ensure an holistic approach is used to assess the fatigue life of your product.

Joint design to ensure best performance for load paths, durability and minimum cost, including manufacturing and raw material costs.

Manufacturing process engineering to ensure low impact on fatigue and minimal residual stress

Material selection optimisation - for manufacture, cost, durability as well as appearance

When to use a FE Model or not!

Before a detailed fatigue study can be completed, a full understanding of the stresses in your product is required. This can be achieved using measurements on a prototype which avoids some of the assumptions in modeling. However, in the early stages of product development no prototype is available, and even if one was, then the time required to prepare it for testing and carry out the test might also be too long for the results to be of any use.

Of course an FE Model is not a panacea for all stress illnesses! It is important that stresses are suitable for fatigue analysis - recall that fatigue is driven by local often plastic stresses. Deciding what to model and what to leave out requires a high level of engineering structural analysis skill and a detailed knowledge of fatigue methods.

At Fatigue-Expert.com our capabilities include linear and non-linear stress analysis, hand calculations, MathCAD, fatigue modeling and optimisation tools and a wide range of presentation and reporting options - HTML, PPT, reports, Video...

So if you need stress analysis - not just any stress analysis - but a fatigue focused stress analysis, then give us a call for a confidential and free discussion about your product development needs.