When grinding concrete floors you may realize when purchasing the concrete grinding shoes that the segments are either soft, medium, or hard bond. What does this mean?
All concrete floors can be of different densities. This is due to the temperature and humidity when the concrete was poured and the MPA of the concrete itself. Also, the age of the concrete can also play a factor in the hardness of the concrete floor too.
The purpose of the bond is to hold the diamond particle in place so it can grind the concrete. As the diamond scrapes along with the concrete, there is quite a lot of friction as you could imagine. The metal bond needs to hold the diamond particle in place to grind the concrete without breaking off until the diamond particle has worn away.
Extra hard concrete is harder to grind as we all know. For the metal bond to hold the diamond particle exposed so it can grind the concrete the bond needs to be soft to wear away to have the diamond particle exposed. The problem with soft bond diamond particles is that it will wear away the diamond faster and the whole segment will wear down quicker.
A hard metal bond holds the diamond particle stronger as the soft concrete grabs onto the segment creating more friction. Due to the increased friction, the diamond particle does not need to be as exposed as on harder concrete.