Sample cutting is an initial and crucial step in the preparation process of metallographic samples. Choosing the appropriate metallographic cutting machine is an effective guarantee for obtaining high-quality metallographic analysis surfaces with fast sample preparation and minimal surface deformation. How to choose an appropriate metallographic cutting machine based on the characteristics of the sample?
A few days ago, after listening to the explanation from the Chain Metallographic Application Engineer, I finally gained knowledge and figured out what precision metallographic cutting machines are and how to use them properly!
Metallographic cutting machines are mainly divided into two categories: grinding wheel metallographic cutting machines and precision metallographic cutting machines. Compared to grinding wheel metallographic cutting machines, precision metallographic cutting machines are more suitable for cutting small, precise, fragile, and superhard samples. This type of sample requires high cutting requirements, with the sample surface required to be as close as possible to the inspection surface, or the cutting loss and notch width required to be as small as possible. Therefore, such samples can only be used with precision metallographic cutting machines, with an accuracy of micrometers. Grinding wheel cutting machines cannot achieve this in any case.
In terms of equipment size, precision cutting machines are much smaller than commonly used grinding wheel metallographic cutting machines in the laboratory, with a cutting blade diameter of generally 3-8 inches (76mm-203mm). The cutting blade can be non abrasion type, such as diamond blade or cubic Boron nitride blade. Of course, wear resistant materials such as ultra-thin alumina grinding wheels or silicon carbide grinding wheels can also be used.
The cutting blades used on precision cutting machines are thin or ultra-thin, and the load during the cutting process is relatively much smaller. The heat generated during cutting and the depth of damage are very small, thus achieving precise cutting of the sample.
Precision cutting machines generally use linear cutting methods, which have less loss, narrower incision width, and smaller damage depth, but relatively longer cutting time. If the sample block is relatively large, it will be time-consuming and inefficient. Therefore, precision cutting machines are only suitable when the sample size is relatively small and the sample incision requirements are high. Otherwise, using a grinding wheel metallographic cutting machine is faster and more efficient.
After understanding these knowledge, have you used your precision metallographic cutting machine correctly? Knowledge always brings us better ways to solve problems. If you have better insights, please share them.