Effect of VC/Cr_3C_2 on microstructure and mechanical properties of Ti(C,N)-based cermets  

VC/Cr_3C_2对Ti(C,N)基金属陶瓷微观组织和力学性能的影响(英文)

作　　者：詹斌[1,2] 刘宁[1,2] 金之铂[1,2] 李其龙[1,2] 石锦罡[1] 

机构地区：[1]合肥工业大学材料科学与工程学院,合肥230009 [2]安徽省有色金属材料与加工工程实验室,合肥230009

出　　处：《Transactions of Nonferrous Metals Society of China》2012年第5期1096-1105,共10页中国有色金属学报（英文版）

基　　金：Project (090414185) supported by the Natural Science Foundation of Anhui Province, China

摘　　要：Effects of VC/Cr3C2 on the microstructure and mechanical properties of Ti（C,N）-based cermets were studied. The microstructure was investigated by means of optical microscopy, X-ray diffractometry as well as scanning electron microscopy in combination with energy dispersive spectrometry. Mechanical properties, such as transverse rupture strength, hardness and fracture toughness, were measured. The results show that there are black core-grey rim structure and white core-grey rim structure in the microstructure. The grains become fine due to the VC/Cr3C2, and the grains of cermet added with 0.75VC/0.25Cr3C2 are refined most remarkably. The black core becomes finer with the increase of VC addition and rim phase becomes thicker with the decrease of Cr3C2 addition. The porosity increases with the increase of VC addition in VC/Cr3C2. Compared with the cermet free of VC/Cr3C2, the transverse rupture strength and hardness of cermets with VC/Cr3C2 are both improved, and the maximum values are both found for the cermet with 0.25VC/0.75Cr3C2. The fracture toughness can be effectively promoted by adding VC/Cr3C2 with an appropriate ratio of VC to Cr3C2, and the maximum value is found for the cermet with 0.5VC/0.5Cr3C2.研究VC/Cr3C2对Ti(C,N)基金属陶瓷微观组织和力学性能的影响。利用光学显微镜、X射线衍射仪和扫描电镜结合能谱仪研究微观组织。测试横向断裂强度、硬度和断裂韧性等力学性能。结果表明:微观组织中存在"黑芯-灰壳"和"白芯-灰壳"结构;由于添加VC/Cr3C2,硬质相晶粒变细,添加0.75VC/0.25Cr3C2的金属陶瓷晶粒细化最明显;黑芯随着VC添加量的增加而变细,壳随着Cr3C2添加量的减少而变厚;孔隙率随着VC/Cr3C2中VC的量增加而增大;横向断裂强度和硬度均升高,并且均在添加0.25VC/0.75Cr3C2时达到最大值;按适当的VC和Cr3C2添加量比例添加VC/Cr3C2可以有效地使断裂韧性升高,并在添加0.5VC/0.5Cr3C2时取得最大值。

关 键 词：Ti（C N）-based cermet VC CR3C2 microstructure mechanical properties 

分 类 号：TG148[一般工业技术—材料科学与工程]