Power of Collective Wisdom Solves ‘Fretting Corrosion’
Now, at this stage I believed that my customer was a victim of either high-mileage fretting corrosion or high-mileage fracturing of cold-solder joints. Either way, “smacking” was the big clue that can temporarily solve either of these issues, and I believed I had a good shot at repairing my customer’s minivan, even though I could not get it to act up. At this point in my detective work, I felt like an attorney attempting to prosecute a murder case without the benefit of a murder weapon – or a body. Luckily, there are precedents for convicting when there is no body, just as you and I have repaired a vehicle or two without locating a tangible root cause.
Fretting
The ASM Handbook on Fatigue and Fracture (Figure 1) defines fretting as: “A special wear process that occurs at the contact area between two materials under load and subject to minute relative motion by vibration or some other force.”
Fretting wear is usually associated with electrical contacts rather than non-electrical things, but fretting and fretting wear occur with both.
What is ‘Fretting Corrosion’?
You may have heard the term fretting corrosion recently and wondered what is going on with this odd-sounding phrase. Fretting is defined by Merriam-Webster as “to pass away the time,” but it also means “to gnaw, chew or corrode,” and it is the second definition that can cause technicians to spend too much time experiencing the first. Fretting corrosion can cause time-consuming intermittent failures in a myriad of vehicle systems, and it can be difficult to find.
