Abstract:In this paper, TiBw/TA19(Si, N) composites were prepared by low-energy mechanical ball milling and Spark plasma sintering technology, and the microstructure and mechanical properties of TiBw/TA19(Si, N) composites were systematically studied by scanning electron microscopy (SEM), XRD diffractometer (XRD), electron probe (EPMA) and electron universal testing machine. The results showed that with the increase of the content of the reinforcing phase, TiBw/TA19(Si, N) composite matrix changed from Wechsler to equiaxed or short sheet structure, Si and N elements were solidly dissolved in TA19 matrix, and the in-situ TiB whiskers (TiBw) were distributed in a quasi-continuous network in the matrix, which effectively inhibited the grain growth and effectively strengthens the grain boundary while retaining the internal plasticity of the grain. When the addition of Si and BN at room temperature was 0.2% and 0.2%, TiBw/TA19(Si, N) composites achieved a good strong plastic matching, and its tensile strength was 1286.9 MPa, the yield strength was 1157.0 MPa, which was increased by 16.3% and 23.6% respectively compared with TA19 titanium alloy, and its elongation was 5.4%. With the increase of the content of the reinforcing phase, TiBw gathered at the grain boundary had a good pinning effect on the matrix structure, but too much TiBw also seriously hindered the connectivity of the matrix during the tensile process, resulting in a significant decrease in tensile plasticity at room temperature. The improvement of the mechanical properties of the composites was mainly due to grain refinement, solution strengthening, and load transfer strengthening.