Amanda:
Hello and welcome to Intertek’s Assurance in Action podcast. I’m Amanda Priya, Marketing Manager at Intertek, and I’m excited to bring you the second episode in our new Chem & Pharma North America series, where we share expert insights on analytical testing, safety, and innovation.
Today, we’re exploring failure analysis with Stephen French, our subject matter expert at Intertek Allentown. Stephen is a licensed Professional Engineer in the state of Pennsylvania and has been with Intertek since 2017, specializing in failure analysis, material and alloy identification, and condition assessment. Prior to joining Intertek, he worked in the same field within the power generation industry and brings more than 35 years of experience as a metallurgical engineer in the electric utility sector.
In this episode, you’ll learn about the general methodology behind metallurgical failure analysis, the types of tests typically used during an investigation, and the common mechanisms that can occur when a component does not perform as expected.
Amanda:
Stephen, welcome to Assurance in Action. It’s great to have you with us today.
To start us off, let’s begin with the foundation of today’s topic. What constitutes a failure and what makes it worth a detailed investigation?
Stephen:
People immediately think of a failure as something falls down, like a bridge, or something breaks or leaks. In actuality, a failure occurs any time when something does not perform the way it was expected or supposed to. You can actually have a failure when something does not actually break; for example, a shear pin in some piece of rotating equipment is designed to break when a specific load is reached. If that pin does not break, the excessive load is transferred to something usually very expensive, which then breaks.
The reason for performing a failure analysis is to identify why the particular component failed so as to avoid it from happening again. If carbon steel was used in an application that requires stainless steel because of a corrosive environment, then using that same carbon steel as the replacement will just result in the same problem further down the road.
A third reason for performing a failure analysis would be to confirm that the failure mechanism is as anticipated, especially when evaluating whether a component is approaching its expected end of life.
Amanda:
That’s a really helpful way to frame it. Building on that, let’s talk about the investigation process itself. What type of tests might be performed in the course of the investigation?
Stephen:
The investigation usually starts with a physical examination of the failed component, either with the naked eye, magnification, or a low-power microscope. Those observations help determine the next steps, such as scanning electron microscopy (SEM) of the fracture surface.
A cross-section through the failure is often the next step, allowing the material to be examined to understand how the fracture moves through the bulk of the component and whether secondary cracks or localized material differences are contributing factors.
Mechanical testing, such as tensile or hardness testing, provides insight into the material’s strength and heat-treated condition. Detailed composition analysis is also used to confirm whether the material matches specification.
For polymers, techniques such as infrared spectroscopy, rheology, and mechanical testing may be used. In corrosion-related failures, X-ray diffraction or Raman spectroscopy can help identify deposits and corrosion products.
Amanda:
That really shows how detailed and methodical the process is. Can you provide some examples of failures you have investigated during your time at Intertek?
Stephen:
One early project involved a platinum-rhodium mesh, similar to a catalytic converter, where the customer was seeing pressure backup issues. Under electron microscopy, the outlet side looked normal, but the inlet side showed jagged, barbed-wire-like structures. The wire diameter had increased significantly due to what we believed was recrystallization caused by high gas-stream temperatures.
Another example involved CPVC pipe failures, which we have seen multiple times. These failures were caused by environmental stress cracking, where a specific chemical environment reacts with the polymer under stress to form branching cracks. In these cases, synthetic ester lubricating oils or foam insulation compounds were the root cause.
Amanda:
Those are great examples of how failure analysis directly impacts prevention. From your experience, what are the most common causes of failure in metallurgy?
Stephen:
A large number of failures are related to corrosion, either as the main driver or as a contributing factor. Mechanical overload can also occur when the applied load exceeds what the component can withstand.
Many components exposed to vibration or cyclic operation can experience fatigue failures, while temperature fluctuations may lead to thermal fatigue cracking. In corrosive environments, corrosion can accelerate and worsen these cracking mechanisms.
Amanda:
Every investigation seems to involve connecting multiple data points. What would you say is the most challenging part of a failure analysis?
Stephen:
Probably the most challenging aspect is putting all of the evidence together in a way that clearly identifies the cause and still makes sense. Every data point collected needs to support the final hypothesis. If one piece of evidence doesn’t fit, the entire scenario needs to be reconsidered.
Amanda:
That investigative mindset is what really brings the science to life. Finally, why is Intertek uniquely positioned to support failure analysis investigations?
Stephen:
Intertek brings together deep metallurgical expertise, advanced instrumentation, and cross-site collaboration. Our Allentown team supports detailed failure investigations, while other Intertek locations contribute specialized capabilities in field support, polymer testing, and advanced materials characterization.
This ability to combine expertise across disciplines allows us to provide clients with both root-cause clarity and practical prevention strategies.
Amanda:
Stephen, thank you so much for joining us and sharing your expertise. Your insights into failure analysis, metallurgy, and real-world investigations have been incredibly valuable.
For our listeners, today’s discussion reinforced an important lesson: when a component does not perform as expected, understanding the root cause is critical to preventing repeat failures, improving safety, and supporting better engineering decisions.
Thank you for joining us for this episode of Intertek’s Assurance in Action podcast. For more information, visit our website Intertek.com to learn more about our Chem & Pharma capabilities.
Until next time, thank you for listening.
