How to judge whether the steel shot meets the use requirements and quality standards?

　　1. Hardness

　　Importance: Hardness is a key indicator to measure the quality and service life of steel shot. Moderate hardness can ensure that the steel shot can effectively remove surface dirt or increase surface roughness during cleaning or strengthening, and will not excessively wear the equipment or produce poor surface morphology due to excessive hardness.

　　Detection method: Usually a hardness tester is used for detection to ensure that the hardness of the steel shot meets the requirements of the product manual or relevant standards. For example, the hardness of steel shot is generally HRC40~50, and the hardness can be increased to HRC57~62 when processing hard metal; the hardness of cast iron shot is HRC58~65.

　　2. Microstructure

　　Importance: The microstructure determines the toughness and fatigue resistance of the steel shot. The ideal microstructure should be able to resist deformation, reduce energy loss, and extend the service life of the steel shot.

　　Detection content: Observe the microstructure of the steel shot to ensure that it is a fatigue-resistant structure such as tempered martensite or tempered troostite. At the same time, brittle carbides should be reduced to avoid premature rupture of steel shots.

　　3. Chemical composition

　　Importance: Chemical composition directly affects the microstructure and properties of steel shots. Appropriate chemical composition can improve the strength, hardness and toughness of steel shots.

　　Test content: Detect the content of beneficial elements such as carbon, silicon, manganese, and harmful elements such as sulfur and phosphorus in steel shots. For example, the chemical composition of high-carbon steel shots is usually: carbon 0.8%~1.2%, manganese 0.6%~1.2%, silicon 0.4%~1.2%, sulfur and phosphorus are both ≤0.05%.

　　4. Fatigue life

　　Importance: Fatigue life is the ability of steel shots to resist breakage during use. Steel shots with long fatigue life can reduce the cost of use and improve economic benefits.

　　Evaluation method: Fatigue life tests are performed by simulating actual use conditions to evaluate the durability of steel shots.

　　5. Physical defects

　　Importance: Physical defects such as cracks and inclusions may cause steel shots to break prematurely during use, reducing their efficiency.

　　Detection method: Use tools such as a magnifying glass or microscope to check whether there are physical defects on the surface and inside of the steel shot.

　　VI. Specifications and shape

　　Importance: Steel shots with uniform specifications and shapes can ensure the consistency of cleaning or strengthening effects.

　　Detection method: Use a sieve to sort the steel shots to ensure that the specifications of the steel shots meet the requirements of use. At the same time, observe whether the shape of the steel shots is regular.

　　VII. Other quality standards

　　Density: Ensure that the density of the steel shots meets the requirements of relevant standards to ensure its stability and durability during use.

　　Moisture content: The moisture in the steel shots may cause them to rust or deteriorate during storage and use, so the moisture content should be strictly controlled.

　　In summary, judging whether the steel shots meet the use requirements and quality standards requires comprehensive consideration of multiple aspects such as hardness, microstructure, chemical composition, fatigue life, physical defects, specifications and shapes, and other quality standards. Through strict testing and evaluation, it can be ensured that the selected steel shots meet the actual use requirements and quality standards.