Common problems and treatment methods of diamond segment
The size does not meet the requirements, the density is not enough, the hardness does not meet the requirements, there is debris in the transition layer, and the strength is not enough.
1. Diamond segment size does not meet the requirements
It is mainly because the pressure is not enough, or the sintering temperature is too low, or the heat preservation and holding time are too short during the sintering, so the diamond segment cannot be flattened, and the diamond segment height is too high; or the indenter size does not meet the requirements. Make the sintered diamond segment too high or too short;
To prevent this problem, the hot pressing parameters must be set correctly. At the same time, workers need to be careful when loading materials to prevent the wrong graphite mold, otherwise the sintered diamond segment may be scrapped and cannot be burned back.
2. Insufficient density and hardness does not meet the requirements
This problem is generally caused by problems in the design of hot-pressing parameters. Such as the design of sintering temperature and holding time is unreasonable make the hardness of the diamond segment is too low or too high which can’t exert the normal performance of the saw blade.
Therefore, the old formula can be sintered according to the previous hot-pressing parameters; for the new formula, not only the theoretical hot-pressing parameters must be inferred, but also appropriate adjustments must be made according to the sintering situation of the first mold to explore the correct hot-pressing parameters.
3. Diamond segment strength not enough
There are two main reasons for the insufficient strength of the diamond segment: 1. The inside of the diamond segment is mixed with impurities, such as graphite particles during mixing raw material; 2. The diamond segment formula design is unreasonable, or the sintering process is unreasonable, resulting in the weak strength of the working layer and the transition layer; the working layer and the transition layer are not strong enough, which causes the diamond segment to be disconnected from the connection between the working layer and the transition layer when the diamond segment is used or the diamond segment is pulled. Generally speaking, the formula of the working layer and the transition layer are the same, but in order to reduce the cost, the diamond segment is generally made of cheap cobalt-free Fe-bond. However, in order to ensure the welding strength, the transition layer formula needs to add an appropriate amount of cobalt, which causes the working layer and the transition layer formula to be different, making their thermal expansion coefficients different, and causing residual shrinkage at the junction of the working layer and the transition layer when the diamond segment cooling, make the strength decrease.
To solve this problem, we must first ensure that the powder is clean and free of dirt; in addition, in order to improve the welding strength of the diamond segment working layer and transition layer, when using transition layers of different formula, it should be considered that elements with similar thermal expansion coefficients are used.