摘要
为了获得性能优异的钛基复合材料和解决单一增强相对性能提升有限等问题,以Ti粉、SiC粉、TiB_(2)粉、C粉为原料,采用粉末冶金法,在不同烧结温度下原位自生制备了(Ti_(5)Si_(3)+TiC+TiB)/Ti复合材料。通过XRD、SEM、万能试验机等设备表征了复合材料的微观组织和力学性能。结果表明:随烧结温度的升高,复合材料的致密度提高,平均晶粒尺寸逐渐增大;烧结温度的升高使增强相数量增加的同时减少了较低烧结温度下的团聚现象。复合材料的洛氏硬度、屈服强度、抗拉强度随烧结温度的升高先增大后减小,断裂应变下降不显著。在1300℃下,(Ti_(5)Si_(3)+TiC+TiB)/Ti具有最佳的综合力学性能,烧结态试样的抗压强度达到最高2435 MPa,屈服强度1649 MPa,洛氏硬度49.1HRC,断裂应变28.7%。分析可知,微米尺寸的TiC、TiB和亚微米尺寸的Ti_(5)Si_(3)增强相的协同作用在显著提高复合材料强度的同时也保持了一定的塑性。(Ti_(5)Si_(3)+TiC+TiB)/Ti复合材料的增强方式以细晶强化、弥散强化和载荷传递强化为主。
In order to obtain titanium matrix composites with excellent performance and to solve the problems such as limited relative performance enhancement of single reinforcement,in situ synthesized TiB,TiC and Ti_(5)Si_(3)reinforced Ti composites at different sintering temperatures were produced by powder metallurgy of Ti powder,SiC powder,TiB_(2)powder and C powder.The microstructure and mechanical properties of the composites were analyzed by XRD,SEM and universal testing machine.The results showed that with the increase of sintering temperature,the density of the composites increased and the average grain size increased gradually.With the increase of sintering temperature,the number of reinforcement increased and the frequency of agglomeration phenomenon which occurs at lower sintering temperature decreased.The Rockwell hardness,yield strength and tensile strength of the composites firstly increased and then decreased as the sintering temperature increased,while there was no obvious decrease in the fracture strain.At 1300℃,(Ti_(5)Si_(3)+TiC+TiB)/Ti composite had the best comprehensive mechanical properties.Moreover,the sintered sample had the highest compressive strength of 2435 MPa,yield strength of 1649 MPa,Rockwell hardness of 49.1HRC and fracture strain of 28.7%.Based on the analysis,the synergistic effect of micron-sized TiC,TiB and sub-micron-sized Ti_(5)Si_(3)reinforcement can significantly improve the strength and maintain plasticity at the same time.The main strengthening methods of(Ti_(5)Si_(3)+TiC+TiB)/Ti composites are fine crystal strengthening,dispersion strengthening and load transfer strengthening.
作者
崔凯强
姜中涛
敬小龙
韩威
CUI Kaiqiang;JIANG Zhongtao;JING Xiaolong;HAN Wei(School of Mechanical Engineering,Chengdu University,Chengdu 610106,China;School of Materials Science and Engineering,Chongqing Institute of Arts and Science,Chongqing Key Laboratory of Materials Surface Interface Science,Chongqing 402160,China)
出处
《材料科学与工艺》
CAS
CSCD
北大核心
2024年第2期89-96,共8页
Materials Science and Technology
基金
重庆市自然科学基金面上项目(CSTB2022NSCQ-MSX0352)
重庆市教育委员会青年项目(KJQN202001306).
