TiC颗粒增强铁基复合材料高温冲击特性及断口分析
Impact Characteristics at Elevated Temperature and Fracture Analysis of TiC Particle Reinforced Fe Matrix Composites
包艳蓉, 李 斌, 刘宗德
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作者单位:华北电力大学 电站设备状态监测与控制教育部重点实验室, 北京 102206
中文关键字:原位合成; TiC颗粒增强; 铁基复合材料; 冲击韧性; 断口分析
英文关键字:in-situ synthesis; TiC particle reinforced; Fe matrix composite; impact toughness; fracture analysis
中文摘要:对自蔓延高温合成/准热等静压法(SHS/PHIP)制备的TiC颗粒增强铁基复合材料进行了高温冲击实验。利用扫描电镜、X射线衍射仪分别对冲击前该复合材料的显微组织和相组成以及冲击后断口形貌和断面物相组成进行了分析。研究表明:随温度的升高,TiC颗粒增强铁基复合材料的冲击韧度增大,断口周围的塑性变形程度增加;室温、550、650和750 ℃下的冲击断口都以沿晶脆性断裂为主,在一些较粗大的TiC颗粒中还出现了穿晶裂纹;高温冲击过程中,该复合材料发生了氧化,断口局部区域出现少量疏松的氧化组织。
英文摘要:The impact test at elevated temperature of TiC particle reinforced Fe matrix composite prepared by self-propagating high-temperature synthesis method combined with pseudo hot isostatic pressing technique (SHS/PHIP) was carried out. The microstructure and phase structures of the composite before the impact test, the morphology and phase composition of the fracture surface after the impact test were analyzed by SEM, X-ray Diffraction, respectively. The results indicate that the impact toughness of TiC particle reinforced Fe matrix composite and the plastic deformation near the fracture surface increase with the increase of temperature. The predominant mode of failure at room temperature, 550, 650 and 750℃ is brittle intergranular fracture, while some cracks propagating through the reinforcing particles can also be observed in some larger TiC particles. The composite is oxidized during the impact test at elevated temperature with a small quantity of loose oxides in some parts of the fracture surface.