What factors can affect the sandblasting effect of a sandblasting machine?

　　1. Surface roughness of workpiece

　　The factors that affect surface roughness include the strength and hardness of the part material, sandblasting diameter, sandblasting angle and speed, and the original surface roughness of the part.

　　All other conditions being equal, the higher the strength and surface hardness values of the component material, the more difficult plastic deformation, the shallower the crater, and the smaller the surface roughness value; The smaller the diameter of sandblasting, the slower the speed, the shallower the crater, and the smaller the surface roughness value; The larger the angle of the spray, the smaller the normal component of the sandblasting speed, the smaller the impact force, the shallower the crater, the higher the tangential speed of sandblasting, the greater the abrasive effect of sandblasting on the surface, and the smaller the surface roughness value.

　　The original surface roughness of the parts is also one of the influencing factors. The rougher the original surface, the smaller the decrease in surface roughness value after sandblasting; On the contrary, the smoother the surface, the rougher the surface becomes after sandblasting. After high-intensity sandblasting of the parts, deep craters not only increase the surface roughness value, but also form significant stress concentration, seriously weakening the strengthening effect of sandblasting.

　　2. The intensity of sandblasting by the sandblasting machine

　　The process parameters that affect sandblasting intensity mainly include: sandblasting diameter, sandblasting flow rate, sandblasting flow rate, sandblasting time, etc. The larger the sandblasting diameter, the faster the speed, and the greater the momentum of the sandblasting collision with the workpiece, the stronger the sandblasting intensity.

　　The sandblasting intensity requires a certain amount of sandblasting time. After a certain period of time, when the sandblasting intensity reaches saturation, extending the sandblasting time will no longer significantly increase the intensity. In the Almen test of sandblasting intensity, the characterization of sandblasting intensity is the increase in specimen deformation.

　　In the Almen test, sandblasting strength is commonly measured using test pieces (for non-ferrous metal testing), A test piece, and C test piece (for higher strength), and the relationship between A test piece and C test piece is approximately three times. If the strength measured by the C test piece is 0.15~0.20tmn, it is equivalent to 0.45~0 of the A test piece 60mm. During the experiment, first measure the original deformation of the test piece, then place the fixture that holds the test piece in place in the sandblasting box and use the same process as the workpiece for spraying. After sandblasting, remove the test piece and measure the deformation arch height of the scene.

　　3. Sandblasting coverage rate

　　Measurement of coverage: Apply a layer of colored glaze or fluorescent glaze on the surface of the workpiece, then sandblast the workpiece according to the process parameters. After sandblasting the surface of the workpiece once, remove it and observe the proportion of residual coating on the surface under a microscope (magnifying glass). If 20% is residual, the sandblasting coverage is 80%. When the residual is only 2%, which means the coverage rate is 98%, it can be considered as complete removal, which means the coverage rate is 100%. At this point, there is a required time. If the coverage rate reaches 400%, it will take four times the required time.

　　The factors that affect coverage include the hardness of the part material, sandblasting diameter, spraying angle and distance, sandblasting time, etc. Under the specified sandblasting intensity conditions, when the hardness of the part is lower than or equal to the standard test piece hardness, the coverage rate can reach 100%; On the contrary, the search coverage rate will decrease.

　　At the same sandblasting flow rate, the longer the distance between the nozzle and the workpiece, the smaller the spraying angle, and the smaller the sandblasting diameter, the shorter the time required to achieve coverage. When sandblasting for strengthening, a suitable sandblasting and spraying angle and distance should be selected to achieve both the required sandblasting strength and coverage.