TEST - Hydrogen Embrittlement
Hydrogen embrittlement is not a new problem, but the ins and outs of hydrogen embrittlement can still be difficult to grasp for those new to dealing with hydrogen. That's why we put together a four-part Ask Swagelok video series detailing what it is, how components can be affected, and can be done to counter embrittlement issues. In the first video, Senior Scientist Buddy Damm gives an overview of hydrogen embrittlement, how it starts, and how it lowers resistance to metal fatigue and fracture.
Ask Swagelok
Topic: Hydrogen Embrittlement
Craig Gifford:
Welcome to Ask Swagelok. I'm Craig Gifford, here today with Buddy Dam, who's the Senior Scientist at Swagelok for metallurgy.
Today, we're going to be talking about hydrogen embrittlement. So let's just start from the beginning, Buddy. What is hydrogen embrittlement?
Buddy Dam:
Hydrogen embrittlement is one of several different types of metallurgical embrittlement phenomena. What embrittlement means is a loss of ductility, or fracture resistance, or fatigue resistance relative to some baseline, right?
Engineering alloys are polycrystalline, meaning they're made up of many crystals. They have second phases, they have inclusions. And when hydrogen is absorbed into an engineering alloy, it tends to want to accumulate at energetically favorable sites—like grain boundaries, like inclusions, and also at places of tensile stress.
So in a component that’s stressed in tension, the hydrogen will preferentially go to those areas.
In simple terms, when that happens, the hydrogen affects the normal process of plastic deformation and reduces the material’s ability to withstand that load.
Craig Gifford:
So how big of a deal is that?
Buddy Dam:
In some cases, it can be catastrophic and result in very early failures and cause a lot of problems—there’s some history around that. But it also can be completely inconsequential.
Through proper design, intelligent material choices, and stress control, you can manage the problem.
Craig Gifford:
Thank you, Buddy. And thank you for joining us for Ask Swagelok.