摘要
本文研究了油淬温度对YG11C和YG20C硬质合金组织及性能的影响。将两种合金在1 000~1 250℃下进行油淬热处理,并于500℃回火,分析了油淬后合金的性能、Co相结构和成分、微观结构和WC晶粒三维形貌。研究结果表明：油淬热处理对YG11C和YG20C合金的密度、硬度和矫顽磁力影响较小,合金的钴磁随油淬温度的升高逐渐降低;油淬热处理不会改变WC的平均晶粒尺寸,但是WC晶粒的三维形貌随油淬温度的升高更加圆钝;随油淬温度的升高,合金中的ε-Co（hcp）含量不断降低,α-Co（fcc）含量不断增加,α-Co（fcc）的峰位也不断偏移,固溶在Co相中的W含量不断增加,Co原子的晶格常数也不断增加;油淬热处理效果与合金的Co含量呈有关,同一油淬温度下,YG20C性能的提升要高于YG11C,YG11C经1 000~1 200℃油淬后,抗弯强度略有提高,冲击韧性略有降低,1 250℃油淬后,抗弯强度略有降低,冲击韧性进一步降低;YG20C经1 000~1 250℃油淬后,抗弯强度和冲击韧性均提高,并在1 200℃达到最大值;YG11C和YG20C的油淬温度均不应超过1 200℃。
The effects of oil quenching temperature on properties and microstructure of YG11C and YG20C cemented carbides were investigated in this paper. YG11C and YG20C cemented carbides were oil quenched between 1 000 ℃ and 1 250 ℃ and tempered at 500 ℃. Properties, Co phase structure and composition, microstructure and three-dimensional WC grain morphology of oil quenched cemented carbides were analyzed. The results show that the oil quenching treatment has little influence on the density, hardness and coercive force of YG11C and YG20C, but the cobalt magnetism of the alloys gradually decreases with the increase of oil quenching temperature. The grain sizes of WC in YG11C and YG20C are not affected by oil quenching treatment, but the three-dimensional WC grain morphologies are more blunt with the increase of oil quenching temperature. With the increase of oil quenching temperature, the content of ε-Co（hp） is decreased, while the content of α-Co （fcc）, solubility of W in Co phase and the lattice constants of Co atoms are increased, and the peak position of α-Co （fec） is constantly offset. The effect of oil quenching treatment is in the same direction with the Co content of the alloy. The improvement of properties of YG20C is higher than that of YG11 under the same oil quenching temperature. The bending strength of YG11C is slightly increased and the impact toughness of YG11C is slightly reduced after oil quenching between 1 000 ℃ and 1 200 ℃, but the bending strength is slightly reduced and the impact toughness of YGllC is further reduced after oil quenching at 1 250 ℃. Both bending strength and impact toughness of YG20C cemented carbide are increased after oil quenching between 1 000 ℃and 1 250 ℃, and reach maximum value at 1 200 ℃. The oil quenching temperature of YG11C and YG20C should not exceed 1 200 ℃.
作者
尹超
郭建中
任跃
Yin Chao Guo Jianzhong Ren Yue Lu Shaowu(State Key Laboratory of Cemented Carbide, Zhuzhou Hunan 412000, China Zhuzhou Cemented Carbide Group Corp. Ltd., Zhuzhou Hunan 412000, China State Key Laboratory of Powder Metallurgy, Central South University, Changsha Hunan 410083, China)
出处
《硬质合金》
CAS
2016年第5期291-299,共9页
Cemented Carbides
关键词
硬质合金
油淬处理
回火
三维形貌
晶格常数
冲击韧性
cemented carbide
oil quenching treatment
tempering
three-dimensional morphology
lattice constants
impact toughness
