摘要
Ti(C_(x),N_(1-x))基金属陶瓷是用不同碳氮比制造的。研究了碳/氮比对芯-环结构和金属陶瓷性能的影响。结果表明,由于孔太多,Ti(C_(0.5),N_(0.5))基金属陶瓷的性能较差。随着碳/氮比的增加,白核/灰环的形成率降低,并且微观结构的均匀性增强。因此,基于Ti(C_(0.7),N_(0.3))的金属陶瓷显示出优异的力学性能,但有少量的孔隙和较低的相对密度。与Ti(C_(0.7),N_(0.3))基金属陶瓷相比,TiC基金属陶瓷在没有N元素的情况下具有较高的相对密度且无孔隙,但其晶粒较粗大。为了获得细晶粒和高密度的显微组织,将0.25%Cr_(3)C_(2)-0.75%VC(质量分数)引入到TiC基金属陶瓷中,获得了优异的硬度、横向断裂强度和韧性。另外,在Ti(C_(0.7),N_(0.3))基金属陶瓷中也添加了0.25%Cr_(3)C_(2)-0.75%VC,但其力学性能低于Ti(C_(0.7),N_(0.3))的金属陶瓷,这是因为细颗粒和反应颗粒与Ti(C,N)发生了急性固溶反应。研究了基于不同C/N比的Ti(C_(x),N_(1-x))基金属陶瓷的切削性能和摩擦性能。结果表明,具有0.25%Cr_(2)C_(3)-0.75%VC的TiC基金属陶瓷在室温下的摩擦系数最低,为0.15,在1000 r/min的高速切削过程中,使用寿命最长。
Ti(C_(x),N_(1-x))-based cermets are fabricated with different ratios of carbon to nitrogen.The effect of C/N ratio on the core-rim structures and properties of cermets was studied.The results indicate that Ti(C_(0.5),N_(0.5))-based cermets possess poor properties due to too many pores.With the increase of C/N ratio,the formation rate of white-core/gray-rims decreases,and the homogeneity of the microstructure is enhanced.Consequently,the Ti(C_(0.7),N_(0.3))-based cermets show excellent mechanical properties,but a spot of voids and low relative density.TiC-based cermets with excellent relative density and non-porosity can be achieved in the absence of N element,which have coarser grain compared with Ti(C_(0.7),N_(0.3))-based cermets.In order to achieve fine grains and high density microstructure,0.25wt%Cr_(3)C_(2)-0.75wt%VC is introduced into the TiC-based cermets.Superior hardness,transverse rupture strength and toughness are achieved.In addition,0.25wt%Cr_(3)C_(2)-0.75wt%VC is also added into the Ti(C_(0.7),N_(0.3))-based cermets,but its mechanical properties are lower than that of the Ti(C_(0.7),N_(0.3))-based cermets without 0.25wt%Cr_(3)C_(2)-0.75wt%VC addition,which is due to acute solid solution reaction of finer and reactive particles with Ti(C,N).The cutting and friction performances of Ti(C_(x),N_(1-x))-based cermets with different C/N ratios were also investigated.The results show that the TiC-based cermets with 0.25wt%Cr_(3)C_(2)-0.75wt%VC exhibit the lowest coefficient of friction which is 0.15 at the room temperature,and the longest service life during high speed cutting at 1000 r/min.
作者
杨露
熊计
郭智兴
刘俊波
苟青山
李相荣
Yang Lu;Xiong Ji;Guo Zhixing;Liu Junbo;Gou Qingshan;Li Xiangrong(School of Mechanical Engineering,Sichuan University,Chengdu 610065,China)
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2021年第12期4272-4281,共10页
Rare Metal Materials and Engineering
基金
National Natural Science Foundation of China(51634006,51901195)
Science and Technology Major Project of Sichuan Province(2020ZDZX0022)
SCU-Pan Zhi Hua Project(2018CDPZH-25)
SCU-Zi Gong Project(2019CDZG-1)
National Science and Technology Major Project of China(2019ZX04007001)。
关键词
芯-环结构
均匀性
切削性能
孔隙
core-rim structure
homogeneity
cutting performance
voids
