Preparation And Performance Of Titanium Boron Carbon Nitride Composite Material

Titanium carbonitride（TiCN）cermet has excellent mechanical properties such as high hardness,abrasion resistance,corrosion resistance and electrical conductivity,making it widely used in many fields.In order to meet the more demanding working environment and improve the performance of titanium carbonitride,many scholars improve the hardness and strength of titanium carbonitride by doping hard phases such as WC,TiB₂ and SiC.There are relatively few studies on improving the toughness,oxidation resistance and conductivity of titanium carbonitride.In this paper,by generating whisker-like h-TiB and doping with B to form a new phase to sinter the titanium-boron-carbon-nitrogen composite material,the relationship between the microstructure and properties of the composite cermet is studied.This article first uses commercial TiCN as the framework material,adds 20 wt.%TiB₂,changes the content of the binder Tipowder to 10 wt.%,20 wt.%,and 30 wt.%,ball mills the mixture,and drys the mixed powder sample by spark plasma sintering（SPS）sintered into a block under set conditions.Grind and polish the sample block,conduct phase analysis and microstructure observation,and conduct mechanical and electrochemical performance tests.Experiments have found that with the increase of Ticontent,the defects and pores of TiCN-TiB₂ composites gradually decrease,and the relative density increases accordingly;When the Ticontent is 30 wt.%,a new phase of whisker-like TiB appears,the content is 19.40 wt.%,and the toughness is further enhanced;The hardness,electrical resistivity,electrochemical stability and corrosion resistance first increase and then decrease with the increase of the amount of titanium doped.The Tipowder is embedded with the penetrating agent,and a certain amount of amorphous C and B powder is added to the penetrating agent,and the powder is calcined at a certain temperature to prepare a mixed powder of TiN,TiCN and TiBCN.Subsequently,a small amount of Tipowder is added to the mixed powder for mixing,drying,and sintering into a block with SPS equipment.The prepared powders and blocks are subjected to phase analysis and microstructure observation,and the block samples are tested for mechanical properties and electrochemical properties.The experimental results show that the prepared TiCN and TiBCN ceramic powders have partially amorphous C and B powders that have not reacted completely.After sintering,the amorphous powders have reacted completely;The relative density of TiCN and TiBCN is slightly worse;TiCN has the highest hardness,which can reach 17.9 GPa,TiBCN is the second,and TiN has the lowest hardness of 12.1 Gpa;The agglomerates are electrically conductive;TiBCN has enhanced oxidation resistance because it contains the B element.