Mainly check the quality of cemented carbide and steel brazed joints and whether there are cracks in the cemented carbide. The normal welding seam should be uniform and free of black spots, the welding seam that is not filled with brazing filler metal is not more than 10% of the total length of the welding seam, and the welding seam width should be less than 0.15mm. The crack tendency of cemented carbide inserts can be checked by the following methods.
① After sandblasting, clean with kerosene first. When there are cracks, there will be obvious black lines on the surface.
② Use 65% kerosene, 30% transformer oil and 5% turpentine to make a solution, add a small amount of Sudan Red, put the pre-inspected tools into the solution and soak for about 10-15 minutes, take it out, rinse with water, and apply a little Check the surface after drying the layered kaolin. If there are cracks on the tool, the color of the solution will show up on the white soil.
