Met Tips: LECO's Metallography Troubleshooting Guide

In this era of incredible plug and play technology, a Video Measuring System or reticle disc for your microscope eyepiece feels like it should be enough to begin accurately measuring metallographic samples, but if you skip your calibration steps, your results could be wildly inaccurate.

My cuts are not as quick or clean as I would like them to be, or my abrasive sectioning wheels wear out too quickly.

It’s frustrating when your cuts take far too long, and even worse when the sectioned specimen is rough and requires excessive amounts of grinding. A consistently sharp blade cuts best, but if it feels like you’re always replacing the blade, maybe the type of blade itself is the problem.

Have you ever let long-cure epoxy mounts cure overnight, only for the setscrew to push into the mount when you went to load it into your grinder/polisher’s fixed specimen holder? When the epoxy is soft, the specimen isn’t secure in the mount or in the specimen holder, and proper grinding and polishing becomes impossible. The eight hour cure time for long cure epoxy means you can’t just whip up a new one; if something goes wrong, you’ve effectively lost an entire day as the replacement also needs eight hours to cure.

But if you left your mounts to cure overnight, shouldn’t that have been more than enough time? What could have gone wrong?

Cracks in your mount are never a welcome sight. While a scratched specimen doesn’t always have a cracked mount, a mount with radial cracks is far more likely to cause a future scratched specimen. While we covered the scratches in an earlier tip, we can’t ignore the cracks.

There is a certain sort of frustration that comes with putting a completed multi-step metallographic preparation beneath the microscope, taking a look, and seeing a discolored or stained surface. While a few types of stains can be ignored, many stains mean something went wrong during the preparation.

Having an abrasive cut-off wheel break in the middle of a cut is scary and can happen even on the best equipment. Replacing the broken blade interferes with your material lab’s smooth workflow. If your sectioning blades are breaking frequently, you might be experiencing some common failures. Below, we outline five of the most frequent causes of a broken blade and how to fix them.

Nothing is more frustrating than when you go to evaluate your sample under a microscope and all you see is scratches across the surface of your specimen. You want your materials lab to run as smoothly as possible and these scratches can slow down your evaluation process, requiring you to start over or redo a sample. The good news is, these scratches can be avoided with the proper precautions, below we take a look at the three main causes for a specimen scratch after polishing and what you can do to avoid them in the future.