Neodymium iron boron casting strip section metallographic analysis sample making method

Abstract

The invention discloses a neodymium iron boron casting strip section metallographic analysis sample making method. The method is carried out by the steps of: 1) sampling: selecting one side that is perpendicular to a sticking roll surface and has clear and visible stria and evenly distributed gaps and breaking it off to obtain a casting strip section, using needle-nose pliers to conduct flatness finishing on the section; 2) casting strip polishing: grinding and polishing the casting strip section on different abrasive paper in order toward a same direction; 3) casting strip section corrosion: using an etching agent to corrode the polished surface; and 4) casting strip section cleaning: employing anhydrous ethanol to clean the corroded surface, and conducting blow drying with ear washing bulbs, thus obtaining a metallographic sample. The method provided by the invention does not involve inlaying, saves the sample making cost, the making process is controlled within 15min in a fastest way, and the qualification rate and efficiency of casting strip section metallographic analysis sample making are greatly improved.

Description

technical field [0001] The invention belongs to the technical field of metallographic sample preparation, and in particular relates to a sample preparation method for metallographic analysis of a section of an NdFeB cast piece. Background technique [0002] The thickness of the sintered NdFeB cast sheet is controlled in the range of 0.2-0.4mm during the production process. It is a brittle, flaky, and irregular material. As the judgment and observation surface, the cross-section has higher requirements on the direction of grinding and polishing. At present, the resin mosaic method is usually used for sample preparation. However, this method has three disadvantages: 1. The analysis cost is high, and special metallographic inlay machines, grinding and polishing machines, bakelite and other resin powders are required as raw materials; The control requirements are high, and the resin powder is prone to shift during the pressing process, resulting in misalignment of the grinding ...

AI Technical Summary

Problems solved by technology

However, this method has three disadvantages: 1. The analysis cost is high, and special metallographic inlay machines, grinding and polishing machines, bakelite and other resin powders are required as raw materials; The control requirements are high, and the resin powder is prone to shift during the pressing process, resulting in misalignment of the grinding and polishing direction, or the cast piece is broken or even broken due to excessive pressing pressure, and the qualified rate of sample preparation is difficult to control; 3. After the resin is cured, it cannot be reused And the sample cannot be easily taken out; 4. The sample preparation cycle is long, the mounting process needs to be pressed, heated and cooled, and it needs to be polished for a long time after mounting, which wastes a lot of time