摘要
研究了中粗WC颗粒含量对Ni-Co粗晶硬质合金微观组织与晶粒尺寸分布的影响,进而讨论了晶粒尺寸分布对硬质合金力学性能的影响。结果显示,中粗WC颗粒可均匀分布在粗晶WC周围阻碍粗晶与粘结相接触,抑制了粗晶粒的快速粗化,降低了合金平均晶粒度与平均自由程,使合金的晶粒尺寸分布均匀性逐渐增加;在压力烧结下所有合金的相对密度均在99.5%以上;矫顽磁力的测量结果均低于计算值,验证了中粗WC颗粒的添加有利于合金晶粒尺寸分布均匀性的增加;随着中粗WC颗粒含量增加,合金平均晶粒度的降低,合金硬度逐渐增加、断裂韧性逐渐降低;微观组织中超粗晶粒逐渐减少,有利于硬质合金抗弯强度和耐磨性的提高。在Ni-Co粗晶硬质合金中加入部分中粗WC颗粒有利于减少晶粒粗化进而提高耐磨性,加入30%中粗WC颗粒时综合性能最好。
The effect of medium coarse WC particles content on the microstructure and grain size distribution of Ni-Co coarse grain cemented carbide was studied,and then the effect of grain size distribution on the mechanical properties of cemented carbide was discussed.The results show that the medium coarse WC grains can be uniformly distributed around the coarse WC grains to hinder the contact between the coarse grains and the bonding phase,which inhibits the rapid coarsening of the coarse grains,reduces the average grain size and average free range of the alloy,and gradually transforms the grain size distribution into a bimodal distribution;the relative densities of all the alloys under pressure sintering are above 99.5%,and the bimodal distribution of the grains size in the microstructure is verified by the phenomenon that the alloys measured coercivities are lower than the calculated.With the increasing in medium coarse WC content,the alloy average grain size decreases,the hardness gradually increases and the fracture toughness decreases;the decrease of super coarse grains content in the microstructure is beneficial to the improvement of flexural strength and wear resistance of the carbide.The appropriate addition of medium coarse WC particles to the Ni-Co coarse grain cemented carbide is beneficial to reduce the grain coarsening and thus improve the wear resistance,and the best comprehensive performance is achieved with 30% medium coarse WC particles.
作者
赵晨浩
徐淑波
李辉
郑君姿
卢庆亮
潘悦飞
Zhao Chenhao;Xu Shubo;Li Hui;Zheng Junzi;Lu Qingliang;Pan Yuefei(School of Materials Science and Engineering,Shandong Jianzhu University,Jinan 250101,China;Die&Mould Technology National Key Laboratory,Huazhong University of Science and Technology,Wuhan 430074,China;Jinan Metallurgical Science Research Institute Co.,Ltd,Jinan 250220,China;Jinan Heavy Industries Group Co.,Ltd,Jinan 250220,China)
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2023年第10期3547-3555,共9页
Rare Metal Materials and Engineering
基金
国家自然科学基金(52001187)
山东省自然科学基金面上项目(ZR2021ME182)。
关键词
Ni-Co粗晶硬质合金
截线法
WC邻接度
晶粒尺寸分布
耐磨性
Ni-Co coarse-grained cemented carbide
truncation method
WC grain adjacency
grain size distribution
abrasion resistance
