Applications Note
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Page 1\n \n \n \n \n \n \nwww.alliedhightech.com \nAllied High Tech Products, Inc. \nCall for more information: 800.675.1118 \nApplications Note\n1200 (P-4000) Grit vs. 1200 Fine Grit \n \n \nDescriptions \n \n1200 (P-4000) grit abrasive discs are \nsputter coated. This causes the silicon carbide \n(SiC) particles to be randomized, which \nprovides more of a “polishing” action. \n1200 (P-4000) grit is recommended for general removal of deformation from a previous step. \n \n1200 Fine grit abrasive discs are \nelectrostatically coated. This causes the SiC \nparticles to stand on end, which provides more \nof a “cutting” action. 1200 Fine grit is recommended for soft materials that smear, step grinding for \nfailure analysis, or when continued material removal is desired (typically after 600 grit). \n \nSurface Finish Comparison \n \n \n \nMaterial Removal and Durability \n \nAluminum rods were encapsulated in green phenolic mounting \npowder, while steel rods were encapsulated in red phenolic \nmounting powder (Figure 2). They were ground separately to a \n600 grit finish using the MetPrep 3™ grinder/polisher with PH-3™ \npower head. \n \nThe mounts were then ground using 1200 (P-4000) grit and \n1200 fine grit to compare material removal using the procedure \noutlined in Table 1. Only one abrasive disc was used for each \ntest; the disc was not changed in order to determine durability \nfor each set of conditions. Material removal was checked every \nminute using a digital indicator measurement system. \nFigure 1: 5X objective, Brightfield. Left: Aluminum rod ground using 1200 (P-4000) grit. \nRight: Aluminum rod ground using 1200 fine grit. \nFigure 2: Aluminum rods (green) and \nsteel rods (red) were mounted in \nphenolic. \n\n\nPage 2\nwww.alliedhightech.com \nAllied High Tech Products, Inc. \nCall for more information: 800.675.1118 \n \n2 \nTable 1: MetPrep 3™ with PH-3™ Grinding Parameters \n \nVariable \nSpecification \nPlaten RPM \n300 \nSample RPM \n150 \nDirection \nComp \nForce (per sample) \n6 lbf \nTime \n1 min \n \nTesting was first performed using three aluminum and steel mounts and then repeated using only one of \neach mount, to compare material removal under different conditions (Figure 3). The data shows that \n1200 fine grit discs remove much more material over the same amount of time than 1200 (P-4000) grit \ndiscs. The removal rate dropped off after 2-3 minutes, indicating that they should be discarded after that \ntimeframe for the best results. \n \n \n \nFigure 3: Graphs showing rates of material removal for the rod samples. \n0\n2\n4\n6\n8\n10\n12\n14\n1\n2\n3\n4\n5\n6\nAverage Material Removal (µm)\nMinute\n1200 (P‐4000) Grit \n3 Al Samples\n1 Al Sample\n3 Steel Samples\n1 Steel Sample\n0\n20\n40\n60\n80\n100\n120\n1\n2\n3\n4\n5\n6\nAverage Material Removal (µm)\nMinute\n1200 Fine Grit \n3 Al Samples\n1 Al Sample\n3 Steel Samples\n1 Steel Sample\n