Development And Performance Evaluation Of The Diamond Carving Grinding Head By Self-propagating High Temperature Synthesis

Conventional sintered diamond tools have insufficient holding force.The high temperature of SHS reaction can form metallurgical bonding between the metal matrix and the diamond grains.Optimize the reactant composition ratio and preparation process by analysis of the process characteristics of SHS reaction.The performances of this grinding heads are tested by comparative experiments.The main contents are as follows:(1)Diamond grinding heads are made by using Al-Ti SHS reaction.The matrix is selected as the Cu-based with Ni.The high frequency induction heating platform is set and makes the corresponding die.Thermodynamic calculations show that the addition of Ni can improve the adiabatic temperature of the system and promote the SHS reaction.(2)The process characteristics of SHS reaction are influenced by forming density,Al-Ti content and Ni content.The experiment shows that the inert material which is not involved in the reaction constitutes the skeleton of the block.Too much reaction leads to collapse of the skeleton.The appropriate Al-Ti content should be below 25% and Ni content should be nearly 10%.(3)The velocity of combustion wave of compacts with diamond decrease and the porosity increase,which is due to the increase of diluent content.The morphology the cross-section and the interface of the diamonds and the matrix are investigated by SEM and EDS.Results show that there are Ti immigrations between the diamonds and the matrix.The metallurgical bonding between Ti and diamonds make relatively high holding force.(4)The performance experiments of three diamond grinding heads demonstrate that the SHS diamond grinding heads are better than normal sintered diamond grinding heads.It is the most sharp when the content of Al-Ti is 25%,but the wear resistance is inferior to the head with 15% Al-Ti content.SHS reaction can increase the utilization ratio of diamonds.