Metallographic sandpaper is a specialized sandpaper used for the preparation and grinding of metallographic analysis samples in physical laboratories. The grinding media include silicon carbide, aluminum oxide, diamond sand, etc. The metallographic sandpaper using diamond sand as the medium is now rarely used due to its low grinding efficiency. Silicon carbide metallographic sandpaper has better water resistance than alumina metallographic sandpaper and is widely used. When choosing, you only need to learn these points, and from then on, choosing metallographic sandpaper really doesn't require anyone, and you can easily choose the appropriate metallographic sandpaper.

    Quality determination of metallographic sandpaper: The technical requirements for sample preparation directly determine the quality of metallographic sandpaper to be selected. For samples with high preparation requirements, it is more suitable to choose domestic well-known brands or imported brands. The price is relatively high, but the quality is good, which can help metallographic engineers prepare high-quality sample surfaces and meet experimental technical requirements. If the technical requirements for general metallographic testing are not high, ordinary quality metallographic sandpaper can be selected to meet the requirements. Most domestic brands can meet the requirements, and the price is also very economical. Therefore, the determination of quality is determined by the sample preparation requirements. Please grasp this point well.


Selection of grinding medium for metallographic sandpaper: Unless there are special requirements, silicon carbide metallographic sandpaper is generally acceptable.

    Selection of shape and size of metallographic sandpaper: For example, the experimental purpose is only to determine the ferrite and other metallographic structures of iron-carbon alloys. The preparation method is generally manual grinding on metallographic sandpaper to prepare samples, which is commonly used in raw material testing or teaching in general processing and production. There is no need for rough grinding with a polishing machine, only a general dry grinding metallographic sandpaper of A4 paper size can be used. The price is quite cheap, costing a few cents per piece, so it is relatively cost-effective for sample preparation.


For metallographic samples with high sample preparation requirements, polishing machines are generally used for rough grinding, fine grinding, and polishing. At this time, the quality of metallographic sandpaper is required to be higher. Based on technical requirements and one's own economic strength, appropriate grades and prices of metallographic sandpaper can be selected. Metallographic sandpaper must match the shape and size of the grinding disc of the polishing machine, which is circular. The diameter can be selected based on the diameter of the grinding disc of the polishing machine. The diameter sizes are 8 inches, 10 inches, and 12 inches, and there are also special small ones that are 3 inches. If there is a clamp for fixing metallographic sandpaper, choose metallographic sandpaper without backing, otherwise choose metallographic sandpaper with backing. Of course, the price of metallographic sandpaper without adhesive is cheaper than that with adhesive. The specific choice is up to you.


The selection of metallographic sandpaper label: It is not so much the label as the thickness of the metallographic sandpaper that is more direct. The particle size of the grinding particles determines the thickness of the metallographic sandpaper. The larger the particle size, the coarser it becomes, and the smaller the particle size, the finer it becomes. On the contrary, the smaller the label number, the coarser the particle size. For example, for metallographic sandpaper labeled P80, the particle size is 188 microns, while for metallographic sandpaper labeled P4000, the particle size is 5 microns. Therefore, how to choose? I will provide you with a comparison table for metallographic sandpaper. Taking the imported metallographic sandpaper from QMAXIS in the United States as an example, you can easily choose it at a glance.

    Looking back at the above introduction, the determination of metallographic sandpaper quality, the selection of metallographic sandpaper grinding medium, the selection of metallographic sandpaper shape and size, and the selection of metallographic sandpaper label are always inseparable from the technical requirements of sample preparation. Once this is clear, you can make a choice. It's really not difficult. With these tips learned, I believe we can choose metallographic sandpaper from now on without seeking help! What do you say?