The determination of cemented carbide defectives are generally divided into carburization, decarburization and hole phenomenon, these are regarded as material quality problems.

If there is no problem for material quality, then will have life impact problem, these are regarded as not used a suitable grade or improper using method.

Cemented carbide can be divided into three types.

P type (YT type), mainly used for cutting and machining of steel.

K type ( YG type), mainly used for cutting and machining of cast iron and nonferrous metals, and mining tools.

M type (YW type), mainly used for cutting and machining of alloy steel, also for steel and cast iron.

In general:

The finer grain size, the higher hardness, the lower strength.  

The more coarse grain size, the lower hardness, the higher strength.

The higher the cobalt content, the lower hardness, the higher strength, the higher welding performance.