It is suggested that the microdiamond of metamorphic rocks resulted from metamorphism and the metamorphic fluid had the importance in microdiamond formation.

The bench test was made to study the friction performance of nano-diamond powder.

Experimental study on laser welding of diamond grains;

The calculating formulas of cutting area of single diamond grain when the diamond circular saw blade rotates along clockwise or counterclockwise with a constant rotational velocity as well as feeding with a constant speed are deduced, and the relationship between the cutting area of diamond grain and sawing parameters is analyzed.

Study on the wear of brazed diamond grits;

The mean protrusion height of diamond grits and grit wear were studied in grinding granite with a brazed diamond wheel.

Sawing is carried out by diamond grits which are embedded into a metal matrix, so whether diamond grits can be tightly held in the metal matrix, and whether their cutting abilities can be fulfilled directly determine the sawing performance .

Kinematics analysis of single diamond grit sawing;

The composition of velocity law of the points in kinematics is led into the solving of the cutting area of single diamond grit.