Why is the fastener pin hardness not enough?
With the increasing demand of society, the use of the performance and quality of fastener pins is also increasing, but many users still ask why the hardness of some fastener pins is still not enough? This may be because fastener pins are in the The hardness of the fastener pins is not enough due to defects in the processing process.
Why is the hardness of the fastener pin not enough? China Standard Parts tells you that the main reasons are as follows:
1. Underheating: The reason for underheating is that the heating temperature is too low or the holding time is insufficient.
2. Overheating: Overheated austenite dissolves excess carbon and alloying elements.
3. Insufficient cooling rate: The workpiece is caused by insufficient cooling rate or part of austenite and pearlite transformation during the quenching process. The reason is that the cooling medium is improperly selected.
4. Improper operation: for example, the stay in the water is too short during double-liquid quenching.
