Cr_3C_2添加量对WC-10Co硬质合金组织与性能的影响
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摘要
采用传统粉末冶金法制备Cr_3C_2添加量(质量分数)为0～4%的WC-10Co硬质合金,通过光学显微镜、扫描电镜与能谱仪对合金微观组织进行观察与分析,测试硬质合金的矫顽磁力、钴磁、密度、横向断裂强度、维氏硬度和断裂韧性,研究Cr_3C_2添加量对WC-10Co硬质合金常规性能的影响,并着重探讨Cr_3C_2对WC晶粒尺寸与均匀性的影响。结果表明:添加Cr_3C_2能有效细化WC-Co硬质合金晶粒,随Cr_3C_2添加量增加,WC晶粒均匀性增加。随Cr_3C_2添加量增加,合金的钴磁呈线性下降,合金密度和断裂韧性降低,维氏硬度和矫顽磁力升高,合金横向断裂强度先升高后降低。Cr_3C_2添加量为0.5%合金钴磁为9.0%,矫顽磁力为19.0 kA/m,密度为14.45 g/cm3,维氏硬度HV30为1 600,抗弯强度和断裂韧性分别为3 920 MPa和10.5MPa?m1/2,该合金具有良好的综合力学性能。
The WC-10 Co cemented carbides with different Cr_3C_2 additive amount(0-4.0%) were prepared by traditional powder metallurgy. The microstructure of the alloy was analyzed by optical microscopy(OM), scanning electron microscopy(SEM) and energy spectrometer. The magnetic force, cobalt magnetic, density, transverse fracture strength, vickers hardness and fracture toughness of the WC-10 Co cemented carbides were tested. The effect of Cr_3C_2 additive amount on the conventional properties was studied. The effect of Cr_3C_2 addition on the grain size and grain uniformity of WC was emphatically discussed. The results show that addition of Cr_3C_2 can effectively refine the grain of WC-Co cemented carbide. With increasing Cr_3C_2 additive amount, the grain uniformity of WC improves, the cobalt magnetism of the alloy decreases linearly, the alloy density and fracture toughness also decrease, the hardness and the magnetic force increase, and the transverse fracture strength increases first and then decreases. The optimal comprehensive mechanical properties of the alloy with the magnetic force of 19.0 kA/m, density of 14.45 g/cm3, hardness(HV30) of 1 600, bending strength of 3 920 MPa, fracture toughness of 10.5 MPa?m1/2 was obtained when the Cr_3C_2 additive amount is 0.5%.
The WC-10 Co cemented carbides with different Cr_3C_2 additive amount(0-4.0%) were prepared by traditional powder metallurgy. The microstructure of the alloy was analyzed by optical microscopy(OM), scanning electron microscopy(SEM) and energy spectrometer. The magnetic force, cobalt magnetic, density, transverse fracture strength, vickers hardness and fracture toughness of the WC-10 Co cemented carbides were tested. The effect of Cr_3C_2 additive amount on the conventional properties was studied. The effect of Cr_3C_2 addition on the grain size and grain uniformity of WC was emphatically discussed. The results show that addition of Cr_3C_2 can effectively refine the grain of WC-Co cemented carbide. With increasing Cr_3C_2 additive amount, the grain uniformity of WC improves, the cobalt magnetism of the alloy decreases linearly, the alloy density and fracture toughness also decrease, the hardness and the magnetic force increase, and the transverse fracture strength increases first and then decreases. The optimal comprehensive mechanical properties of the alloy with the magnetic force of 19.0 kA/m, density of 14.45 g/cm3, hardness(HV30) of 1 600, bending strength of 3 920 MPa, fracture toughness of 10.5 MPa?m1/2 was obtained when the Cr_3C_2 additive amount is 0.5%.
引文
[1]HUANG S G,VANMEENSEL K,BIEST O V,et al.Binderless WC and WC-VC materials obtained by pulsed electric current sintering[J].International Journal of Refractory Metals&Hard Materials,2008,26(1):41-47.
[2]程继贵,王华林,夏永红,等.功能梯度硬质合金和金属陶瓷材料研究的新进展[J].材料导报,2000,14(4):16-18.CHENG Jigui,WANG Hualin,XIA Yonghong,et al.New progress in the research of functionally graded cemented carbide and cermet[J].Materials Review,2000,14(4):16-18.
[3]SPINGS G E.A history of fine grained hardmetal[J].International Journal of Refractory Metals and Hard Materials,1995,13(5):241-255.
[4]铃木寿.WC-Cr3C2-15%Co硬质合金的组织和机械性能[J].粉末冶金,1984,31(2):56-59.SUZUKI H.WC-Cr3C2-15%Co cemented carbide microstructure and mechanical properties[J].Powder Metallurgy,1984,31(2):56-59.
[5]史晓亮.超细硬质合金晶粒生长抑制剂VC、Cr3C2作用机理的研究[J].硬质合金,2006,23(4):193-197.SHI Xiaoliang.Study on the mechanism of effect of VC and Cr3C2 on grain growth inhibitors of superfine cemented carbide[J].Cemented Carbide,2006,23(4):193-197.
[6]李海艳.Cr3C2对WC-6.5%Co硬质合金组织和性能的影响[J].热处理,2010,25(2):31-34.LI Haiyan.Effect of Cr3C2 on Microstructure and properties of WC-6.5%Co cemented carbide[J].Heat Treatment,2010,25(2):31-34.
[7]张守全.碳含量对WC-10Co-0.6Cr3C2硬质合金组织结构与性能的影响[J].粉末冶金材料科学与工程,2014,19(3):446-450.ZHANG Shouquan.Effect of carbon content on microstructure and properties of WC-10Co-Cr3C2 cemented carbide[J].Materials Science and Engineering of Power Metallurgy,2014,19(3):446-450.
[8]PETER Warbichler,HOFER F,GROGGER W.(Austria).EFTEMH-EELS characterization of cemented carbide adding VC and Cr3C2[J].International Journal of Refractory Metals and Hard Materials,2003,19(2):4-9.
[9]ROEBUCK B.Terminnology,testing,properties,imaging and models for fine grained hard materials[J].International Journal of Refractory Metals&Hard Materials,1995,13(5):265-279.
[10]李广生.超细WC-Co硬质合金的磁性能与金相分析[J].中国钨业,2008,23(2):33-35.LI Guangsheng.Magnetic properties and metallographic analysis of superfine WC-Co cemented carbide[J].China Tungsten Industry,2008,23(2):33-35.
[11]王崇琳.相图理论及其应用[M].北京:高等教育出版社,2008:91-95.WANG Chonglin.Phase Diagrams and Its Application[M].Beijing:Higher Education Press,2008:91-95.
[12]周书助.硬质合金生产原理和质量控制[M].北京:冶金工业出版社,2014:46-47.ZHOU Shuzhu.Production Principle and Quality Control of Cemented Carbide[M].Beijing:Metallurgical Industry Press,2014:46-47.
[2]程继贵,王华林,夏永红,等.功能梯度硬质合金和金属陶瓷材料研究的新进展[J].材料导报,2000,14(4):16-18.CHENG Jigui,WANG Hualin,XIA Yonghong,et al.New progress in the research of functionally graded cemented carbide and cermet[J].Materials Review,2000,14(4):16-18.
[3]SPINGS G E.A history of fine grained hardmetal[J].International Journal of Refractory Metals and Hard Materials,1995,13(5):241-255.
[4]铃木寿.WC-Cr3C2-15%Co硬质合金的组织和机械性能[J].粉末冶金,1984,31(2):56-59.SUZUKI H.WC-Cr3C2-15%Co cemented carbide microstructure and mechanical properties[J].Powder Metallurgy,1984,31(2):56-59.
[5]史晓亮.超细硬质合金晶粒生长抑制剂VC、Cr3C2作用机理的研究[J].硬质合金,2006,23(4):193-197.SHI Xiaoliang.Study on the mechanism of effect of VC and Cr3C2 on grain growth inhibitors of superfine cemented carbide[J].Cemented Carbide,2006,23(4):193-197.
[6]李海艳.Cr3C2对WC-6.5%Co硬质合金组织和性能的影响[J].热处理,2010,25(2):31-34.LI Haiyan.Effect of Cr3C2 on Microstructure and properties of WC-6.5%Co cemented carbide[J].Heat Treatment,2010,25(2):31-34.
[7]张守全.碳含量对WC-10Co-0.6Cr3C2硬质合金组织结构与性能的影响[J].粉末冶金材料科学与工程,2014,19(3):446-450.ZHANG Shouquan.Effect of carbon content on microstructure and properties of WC-10Co-Cr3C2 cemented carbide[J].Materials Science and Engineering of Power Metallurgy,2014,19(3):446-450.
[8]PETER Warbichler,HOFER F,GROGGER W.(Austria).EFTEMH-EELS characterization of cemented carbide adding VC and Cr3C2[J].International Journal of Refractory Metals and Hard Materials,2003,19(2):4-9.
[9]ROEBUCK B.Terminnology,testing,properties,imaging and models for fine grained hard materials[J].International Journal of Refractory Metals&Hard Materials,1995,13(5):265-279.
[10]李广生.超细WC-Co硬质合金的磁性能与金相分析[J].中国钨业,2008,23(2):33-35.LI Guangsheng.Magnetic properties and metallographic analysis of superfine WC-Co cemented carbide[J].China Tungsten Industry,2008,23(2):33-35.
[11]王崇琳.相图理论及其应用[M].北京:高等教育出版社,2008:91-95.WANG Chonglin.Phase Diagrams and Its Application[M].Beijing:Higher Education Press,2008:91-95.
[12]周书助.硬质合金生产原理和质量控制[M].北京:冶金工业出版社,2014:46-47.ZHOU Shuzhu.Production Principle and Quality Control of Cemented Carbide[M].Beijing:Metallurgical Industry Press,2014:46-47.