第2期 倪丁瑞等：原位混杂增强钛基复合材料的制备与组织分析 .111, A Tic/Ti MMC produced by combustion synthesis.Scripta Sin.1999,35.536 Mater,1996,35(8):1007 [14]Chrysanthou A,Chen Y K.Vijayan A.et al.Combustion syn- [13]Li W J.Zhang X N,Zhang D,et al.Growth mechanism of re- thesis and subsequent sintering of titanium"matrix composites.J inforcement inin situ processed TiC/Ti composites.Acta Metall Mater Sci,2003,38:2073 Microstructure and fabrication of hybrid in situ titanium matrix composites NI Dingrui,GENG Lin,ZHENG Zhenzhu Materials Science and Engineering School.Harbin Institute of Technology.Harbin 150001,China ABSTRACT The feasibility of fabrication in situ TiB and TiC hybrid titanium matrix composites based on a Ti B4C C system was analyzed in theory and chemical reactions among the blended powders of Ti,B4C and C powders during the heating process was studied by differential scanning calorimetry(DSC).The results of DSC show that drastic exothermal reactions take place during the course of heating,which indicates that some new phases are formed.Xray diffraction (XRD)patterns of the as-sintered composites reveal that TiB and TiC would be formed in the as-sintered composites and the peak intensity of TiC increases with increasing amount of graphite powder,showing that both the reactions of Ti B4C and TiC systems have taken place completely within the range of 940~1150C.OM and SEM results show that rodlike TiB whiskers and equiaxed TiC par- ticulates distribute uniformly in titanium matrix.It is suggested that in situ TiB whisker and TiC particulate hy- brid reinforced titanium matrix composites can be prepared by hot pressing of a Ti B4C C system. KEY WORDS titanium matrix composites(T MCs);reactive hot pressing;microstructure;in situ formation; hybridA Tic／Ti MMC produced by combustion synthesis．Scripta Mater‚1996‚35（8）：1007 ［13］ LüW J‚Zhang X N‚Zhang D‚et al．Growth mechanism of re￾inforcement in in situ processed TiC／Ti composites．Acta Metall Sin‚1999‚35：536 ［14］ Chrysanthou A‚Chen Y K‚Vijayan A‚et al．Combustion syn￾thesis and subsequent sintering of titanium-matrix composites．J Mater Sci‚2003‚38：2073 Microstructure and fabrication of hybrid in situ titanium matrix composites NI Dingrui‚GENG L in‚ZHENG Zhenz hu Materials Science and Engineering School‚Harbin Institute of Technology‚Harbin150001‚China ABSTRACT The feasibility of fabrication in situ TiB and TiC hybrid titanium matrix composites based on a Ti －B4C－C system was analyzed in theory and chemical reactions among the blended powders of Ti‚B4C and C powders during the heating process was studied by differential scanning calorimetry （DSC）．The results of DSC show that drastic exothermal reactions take place during the course of heating‚which indicates that some new phases are formed．X-ray diffraction （XRD） patterns of the as-sintered composites reveal that TiB and TiC would be formed in the as-sintered composites and the peak intensity of TiC increases with increasing amount of graphite powder‚showing that both the reactions of Ti－B4C and Ti－C systems have taken place completely within the range of940～1150℃．OM and SEM results show that rodlike TiB whiskers and equiaxed TiC par￾ticulates distribute uniformly in titanium matrix．It is suggested that in situ TiB whisker and TiC particulate hy￾brid reinforced titanium matrix composites can be prepared by hot pressing of a Ti－B4C－C system． KEY WORDS titanium matrix composites （T MCs）；reactive hot pressing；microstructure；in situ formation； hybrid 第2期 倪丁瑞等： 原位混杂增强钛基复合材料的制备与组织分析 ·111·