Get talking - The value of materials failure investigation

Materials World magazine
,
6 Aug 2019

Failure analysis demands high levels of research and accuracy, but providing value at competitive prices is increasingly challenging. DNV GL Senior Consultant Materials and IOM3 Materials Failure Investigation Group Chair, Jeffrey Stephen Jones MIMMM, discusses the importance of education and best practice.

Modern industry has an ongoing drive to exploit the many benefits arising from the electronic revolution. The use of microprocessors has increased the accuracy of process control and improved reaction times to transient conditions. In a laboratory environment, software has allowed traditional optical microscopes to be used to produce 3D images, while in design phases, modelling systems are used for tailoring the systems built to achieve greater efficiencies. With all of these improvements, however, failures still occur. Due to this, in many industries the importance of data and the understanding of it takes second place to financial necessity. A common response to a failure is extracting a single component of a mechanism and sending it to
a laboratory with the question, ‘What happened to
this?’. The aim of failure analysis is to determine what happened, place blame on a party and enable a compensation claim to be submitted.

Quotations are often requested from a number of laboratories and as a general rule, these prompt two types of response – the cheap and the expensive option. Aside from the commercial considerations, these approaches are generally a mechanism identification exercise or a failure investigation. The latter is the more expensive option and therefore often not pursued. While for the simpler cases this may be a wise choice – as identification of the mechanism may provide sufficient information to allow a remedial action to be taken – in more complex cases it may prove to be more costly in the medium to long term.

This is an ongoing area of contention in the failure analysis industry. There is always a question about what is fit for purpose in any given failure scenario versus the optimum amount of money to extract from any given client. The financial returns are a given priority in a competitive environment and we, in the failure investigation industry, as with many others, can only justify our existence in terms of revenue. This being the case, a race to the lowest price is all too often the result.

The cure for this is not straightforward so the importance of establishing an ethical balance is the responsibility of the organisation or individual involved. As with most transactions, it may also come down to sales technique which, for many older engineers is akin to assault and battery as they are meant to engineer not to sell.

One answer to this may be client education. The essence of this is to inform the end user of the benefits of following varying investigation routes. This requires an investment in time in the hope of future reward, but generally such an approach is not regarded as business friendly. Another method is to approach the problem as a non-partisan third party and put the information in the public domain. This has been done in the past via various standard body documents, including ASTM E2733, IEC 60812, ASTM G161, CEN/TS 843-6 and EN62470. These documents are seldom if ever looked at by anyone except practitioners, who use them as a supporting reference in their work. Efforts to describe the process in comprehensible terms have been made by major bodies, such as ASM International. These are valid attempts, but to date it would appear they have had very little market penetration.

Delivering value

The question, therefore, becomes ‘what is the best route to open a discussion that informs people generally?’. The problem is how to attract the attention of a sufficiently wide range of people or to circulate the information that impartial advice can be obtained. A suggestion that has been mooted is a disaster road show. It is reasoned that nothing attracts a crowd like scenes of devastation or a good flash and bang show. Naturally, one of the sticking points in the process is, although those involved in its pursuit are capable in many aspects, they have the limitation in the information age of not being the greatest exponents of market interpretation and manipulation. Furthermore, because there is a wide range of practitioners in the industry who would like to be stakeholders in the process of education, and not always with the most noble of motivations, is reaching a consensus first of concept and then of content. This is challenging, given the diversity of involvement.

As a response to this set of challenging and sometimes contradictory requirements, the IOM3 Materials Failure Investigation Group (MFIG) has been formed. It consists of a group of around 25 people, all involved in failure investigation aiming to start an education process in a neutral environment. The group has illustrated the huge diversity of materials types and the necessity for treating each type differently, prior and during the process of investigation. At the first formal meeting, presentations were put forward on methods of evidence preservation and problems arising from client perceptions of how to manage the process. To extend this further, a high-level document is being prepared on how to preserve evidence post-failure. This is an important first step in getting knowledge to diffuse from the concentrated expertise of older people to younger practitioners and those who need to know. It is a helpful practice to cascade experience, generally by mentoring, where younger or new people are paired with experienced staff in order to gain knowledge.

It is also useful to try to foster a partnering approach with clients. In purely technical aspects, this involves trying to gain an understanding of the client’s plant process so that a context for failure investigation can be established. This approach can be problematic as the generation of context can take time, especially for the highly specialised graduates arriving in industry with little practical experience. Time is an expensive commodity, but this supports establishing solid relationships in the long term, and allows for the acquisition of data over time which, in the current climate of digital innovation, enables companies to offer solutions based on emerging data trends and to pre-emptively forestall failures.

Communicating support

At this stage, a failure investigation group would set out to teach clients based on the manifest errors on receipt of specimens. Classic errors are still a daily trial as inexperienced clients may demonstrate how pieces of fractured components fit together or rub fracture surfaces with their hands. On these occasions, if possible, it is useful to show clients around a testing and analysis laboratory to demonstrate the in-depth materials examination process during a typical failure investigation.

Metallographic specimens or scanning electron microscopy (SEM) samples with handling damage can then be shown to the client. This shows how to handle failed components so as not to damage the evidence. Hands on demonstrations of these factors have a positive effect in that clients can see what happens to materials which can drive home the complexities of failure investigation more effectively than talking.

An added benefit is establishing a connection between the investigators and the clients, which greatly eases communication.

Additionally, it is important to encourage participation in forums about the development of new methodologies of both investigation and system integrity maintenance by means of joint industry projects. The outcomes of these projects remains proprietary to the participant for a period after which they are released into the wider industrial environment in the form of best practice documents and associated guidelines. Greater crossover between the company divisions is necessary to establish a wider audience, as the skills involved in failure investigation can be applied to almost any field of industrial endeavour.

Within the MFIG group, work is underway to establish how to rouse interest in people who may potentially use this knowledge, and others who may be interested in either contributing knowledge or learning. As always, this takes time, which is a costed resource. We, therefore, soldier on trying to build momentum that will lead to a stable base for further developments.

Finally, if you have the misfortune to have a failure of some plant system or component, ask yourself if you want or need to understand possible further ramifications of the failure. It may be that your own expertise will allow an extrapolation of a mechanism identification to the ramifications to the allied system. If this is not the case, in the long term it may well pay to spend more to understand the problems that may affect your system and prevent failures in future.


Read more about failure analysis and testing by visiting the IOM3 Materials Failure Investigation Group here: bit.ly/32oXite