Fabrication And Properties Of The In-situ TiN_x Particle Reinforced Cu Composites

Considering the high yield strength and high ductility performance requirements for Cu matrix composites in the current applications,this paper prepared the in-situ TiN_x particle reinforced Cu matrix composites by means of adding Ti₂AlN ceramics as the poineer materials and studied the relevant technical and scientific problems in the TiN_x/Cu system.Regarding the reaction behaviors of Ti₂AlN and Cu at high temperature,the in-situ TiN_x particle reinforced Cu matrix composites were fabricated through hot-pressing.By X-ray diffraction?XRD?,scanning electron microscope?SEM?and Energy Dispersive Spectrometer?EDS?observation,the sintering parameters of the high purity Ti₂AlN,the phase and the microstructure changes of TiN_x/Cu composites via different sintering processes were explored,and some of its properties were characterized.The results showed that:?1?The mole ratio of Ti/Al/TiN,the raw material powder proportion had an influence on the purity of Ti₂AlN powders.The results indicated that the purity of the Ti₂AlN powders was highest after holding 0.5h in the Ar condition when heating the Ti/Al/TiN powders in the ratio of 1:1:0.95 to 1450? at the heating rate of 15 ?/min.?2?The study on the reaction behaviors of Ti₂AlN and Cu found that Cu and Ti₂AIN will occur reaction at a high temperature,Ti₂AlN particles break up into TiN_x particles,and Al is formed into the matrix of Cu,which will form into Cu?Al?solid solution.?3?In the TiN_x/Cu composites prepared by the reaction sintering of Ti₂AlN and Cu at 1150?,the micro scale Ti₂AlN particles decomposed into sub-micro and nano size TiN_x particles.The TiN_x particles would distribute in the matrix uniformly.When the volume contents of Ti₂AlN were 10%?40%,the initial Ti₂AlN particles would almost decompose into TiN_x completely.?4?The holding time and the Ti₂AIN volume contents had an influence on the microstructure of the TiN,/Cu composites.When the volume content of the Ti₂AlN was 30%,the distribution of the TiN_x particle reinforcements in the matrix would become more and more homogeneous with a longer holding time.The TiN_x phase particle got more and more with the initial Ti₂AlN content increases at the same holding time.?5?The TiN_x/Cu composites has good mechanical properties.The compression fracture strength and compression fracture strain of the TiN_x/Cu composites with 30 vol.%Ti₂AlN were improved from 1060MPa and 24.93%to 1332MPa and 38.68%as the holding time increased from Oh to 2h.The flexure strength enhanced from 630MPa to 785MPa.?6?As the volume of the initial Ti₂AlN increases,the density of composite materials decreases,the resistivity,vickers hardness and compression yield strength increase.When initial Ti₂AlN volume content increased from 10%to 40%,the density of TiN_x/Cu composites from 8.25g/cm³ to 7.31g/Cm3,Vickers hardness increased from 1.03GPa to 3.03GPa,compress yield strength increased from 150MPa to 625MPa,the fracture toughness increased from 8.08MPa.m^1/2 to 15.80MPa.m^1/2.