铬添加量对Ti(C,N)基金属陶瓷结构和磁学性能的影响

Effect of Cr Addition Amount on Microstructure and Magnetic Properties of Ti(C,N)-based Cermets

以TiC粉、镍粉、TiN粉、碳粉以及铬粉为原料,采用粉末冶金法制备TiC-10TiN-xCr-30Ni-4C(x=0,2,4,6,8,物质的量分数/%)金属陶瓷,研究了铬添加量对金属陶瓷结构、磁学性能以及力学性能的影响。结果表明:随着铬添加量的增加,金属陶瓷的密度增大,Ti(C,N)陶瓷相呈黑芯-灰环结构且黑芯和灰环的成分变得更均匀,Ti(C,N)陶瓷相颗粒细化,镍基黏结相的晶格常数先增加后略微减小。当铬物质的量分数不大于2%时,金属陶瓷呈铁磁性,随着铬添加量的继续增加,金属陶瓷具有室温无磁性的特性。随着铬添加量的增加,金属陶瓷的室温最大磁化率先降后升,饱和磁化强度和剩余磁化强度均降低,且当铬的物质的量分数大于2%时,均保持为0。随着铬添加量的增加,金属陶瓷的抗弯强度降低,硬度升高。铬添加物质的量分数为4%时,金属陶瓷的综合性能最好,具有室温无磁性、最低的室温最大磁化率(1.85×10^(-7)m^(3)·kg^(-1))、较高的抗弯强度(1 094 MPa)和硬度(88.1 HRA)。

With TiC,Ni,TiN,C and Cr powders as raw materials,TiC-l0TiN-x Cr-30Ni-4C(x=0,2,4,6,8,molar fraction/%) cermets were prepared by powder metallurgy,and the effects of Cr addition amount on the structure,and magnetic and mechanical properties of the cermets were investigated.The results show that with the increase of Cr addition amount,the density of cermets increased,the Ti(C,N) ceramic phase showed black core-ash ring structure,the composition of black core and ash ring became more uniform,the particles of Ti(C,N) ceramic phase were refined,and the lattice constant of Ni-based binder phase firstly increased and then slightly decreased.When the molar fraction of Cr was not greater than 2%,the cermets were ferromagnetic,and as the addition amount of Cr continued to increase,the cermets had the non-magnetic characteristics at room temperature.With the increase of Cr addition amount,the maximum magnetic susceptibility at room temperature of cermets first decreased and then increased,and the saturation magnetization and remanent magnetization first decreased and then remained 0 under the molar fraction of Cr greater than 2%.With the increase of Cr addition amount,the flexural strength of the cermets decreased,and the hardness increased.When the molar fraction of Cr was 4%,the cermet had the best overall properties with non-magnetic properties at room temperature,the lowest room temperature maximum magnetic susceptibility of 1.85×10^(-7) m^(3) · kg^(-1)and the high bending strength of 1 094 MPa and hardness of 88.1 HRA.