Ti(C,N)含量对硬质合金脱β层的形成及其CVD涂层刀具切削性能的影响
|
摘要
本文通过改变原料中Ti(C,N)的含量(0.5%和1.5%)(质量分数,下同),采用一步烧结法制备了WC-Ti(C,N)-Nb C-Co脱β层硬质合金,并通过化学气相沉积(CVD)技术制备Ti N/MT-Ti CN/Al2O3涂层硬质合金,研究的目的是比较Ti(C,N)含量的微量变化对其脱β层硬质合金的微观组织和物理力学性能,以及其涂层刀具车削45#钢的使用寿命的影响。研究结果表明:在两种合金的表层均形成了脱β层,随着Ti(C,N)含量从0.5%增加至1.5%,脱β层厚度从11μm增加至35μm,另外,WC平均晶粒度从1.97μm减少至1.60μm;矫顽磁力HC和维氏硬度HV30提高,合金密度D和断裂韧性KIC降低。涂层刀片的切削试验结果表明:高Ti(C,N)含量制备的涂层刀片的耐磨性略微降低,而抗冲击性能明显提高。
A gradient sintered WC-Ti( C,N)-Nb C-Co cemented carbides were fabricated with two different Ti( C,N)contents( 0. 5 % and 1. 5%) and by one-step sintering procedure,and were coated with the Ti N / MT-Ti CN / Al2O3 coating using chemical vapor deposition( CVD). The effects of the variation in Ti( C,N) content on the resulting microstructures and the mechanical behavior of gradient cemented carbide and its cutting performance of coated inserts in turning of 45 # steel were studied. The results show that both the alloys create a surface zone depleted of cubic carbides,with the increase of Ti( C,N) content,the zone width increases from 11μm to 35μm and the average WC grain size decreases from 1. 97 μm to 1. 60 μm; meanwhile,hardness( HV30) and coercive force( Hc) increase,while fracture toughness( KIC) and density decrease. The cutting tests demonstrate that the coated gradient inserts with a higher Ti( C,N) content have a slightly decreased wear resistance,but obviously improve impact resistance.
A gradient sintered WC-Ti( C,N)-Nb C-Co cemented carbides were fabricated with two different Ti( C,N)contents( 0. 5 % and 1. 5%) and by one-step sintering procedure,and were coated with the Ti N / MT-Ti CN / Al2O3 coating using chemical vapor deposition( CVD). The effects of the variation in Ti( C,N) content on the resulting microstructures and the mechanical behavior of gradient cemented carbide and its cutting performance of coated inserts in turning of 45 # steel were studied. The results show that both the alloys create a surface zone depleted of cubic carbides,with the increase of Ti( C,N) content,the zone width increases from 11μm to 35μm and the average WC grain size decreases from 1. 97 μm to 1. 60 μm; meanwhile,hardness( HV30) and coercive force( Hc) increase,while fracture toughness( KIC) and density decrease. The cutting tests demonstrate that the coated gradient inserts with a higher Ti( C,N) content have a slightly decreased wear resistance,but obviously improve impact resistance.
引文
[1]Fallqvist M,Olsson M,Ruppis S,et al.Abrasive wear of multilayerκ-Al2O3-Ti CN CVD coatings on cemented carbide.Wear,2007,263(1/6):74-80
[2]Konyashin I Y.Improvements in reliability and serviceability of cemented carbides with wear-resistant coatings.Materials science and engineering,1997,A230:213-220
[3]Chen Li,Wu Enxi,Li Jia,et al.Effects of gradient structure on the microstructure and properties of coated cemented carbides.Journal of University of Science and Technology Beijing,2006,13(4):363-367
[4]Jose G,Reinhard P.The role of cemented carbide functionally graded outer-layers on the wear performance of coated cutting tools.Int.Journal of Refractory Metals and Hard Materials,2013,36:52-59
[5]Konigshofer R,Eder A,Lengauer W,et al.Growth of the graded zone and its impact on cutting performance in high-pressure nitrogen modified functionally gradient hardmetals.Journal of Alloys and Compounds,2004,336(1/2):228-332
[6]张武装,刘咏,贺跃辉,等.Ti(C,N)含量对硬质合金梯度结构和性能的影响.稀有金属与硬质合金,2005,33(2):28-30
[7]温光华,贺跃辉,王社权,等.Ti(C,N)的碳氮比及粒度对脱β层梯度硬质合金的影响.硬质合金,2009,20(4):201-205
[8]Xiong J,Guo Z X,Yang M,et al.Effect of ultra-fine Ti C0.5N0.5on the microstructure and properties of gradient cemented carbide.Journal of Materials Processing Technology,2009,209(12):5293-5299
[9]Ekroth M,Frykholm R,Lindholm M,et al.Gradient zones in WCTi(C,N)-Co-based cemented carbides-experiment study and computer simulations.Acta Materials.2000,48(9):2177-2185
[10]Frykholm R,Ekroth M,Jansson B,et al.A new labyrinth factor for modelling the effect of binder volμme fraction on gradient sinteing of cemented carbides.Acta Materials,2003,51:1115-1121
[11]Frykholm R,Jansson B,Andren H O.The influnce of carbon content on formation of carbo-nitride free surface layers in cemented carbides.International Journal of Refractory Metals and Hard Mateials,2002,20(5):345-353
[12]Frykholm R,Ekroth M,Jansson B,et al.Effect of cubic phase compositon on gradient zone formation in cemented carbides.International Journal of Refractory Metals and Hard Mateials,2001,19(4):527-538
[13]史留勇,刘义敏,张守全,等.脱β层梯度硬质合金的制备及组织结构.粉末冶金材料科学与工程,2011,16(1):67-72
[14]Roebuck B,Bennette G,Gee M G.Grain size mea-surement methods for WC/Co hardmetals.In:Bildstein H,Eck R.editors.Proc 13th Int Plansee seminar,Metallwerk Plansee,Reutte,1993,2:273-292
[15]Shetty D K,Wright P N,Glauer A H.Indentation fracture of WCCo cerments.Journal of Materials Science,1985:20(5):1873-1882
[16]Schwarzkopf M,Exner H E,Fischmeister H F.Kinetics of compositional modification of(W,Ti)C-WC-Co alloy surfaces.Materials science and engineering A,1988,105/106:225-231
[17]Ashe N G,Neethling J H,Berndt P R et al.A comparison of the microstructures of WC-VC-Ti C-Co and WC-VC-Co cemented carbides.International Journal of Refractory Metals and Hard Mateials,2007,25(3):207-213
[18]Weidow J,Zachrisson J,Jansson B et al.Characterization of WCCo with cubic carbide additions.International Journal of Refractory Metals and Hard Mateials,2009,27(2):244-248
[19]李勇,龙坚战.WC-Co硬质合金磁性能与晶粒度之间的关系.硬质合金,2010,27(4):195-198
[20]吴悦梅,熊计,赖人铭.碳含量对WC-Co硬质合金的显微组织的影响及其控制.硬质合金,2008,25(3):179-185
[21]刘昌斌,夏长清,李艳鑫.脱β层厚度对CVD涂层硬质合金性能的影响.硬质合金,2011,28(2):83-87
[2]Konyashin I Y.Improvements in reliability and serviceability of cemented carbides with wear-resistant coatings.Materials science and engineering,1997,A230:213-220
[3]Chen Li,Wu Enxi,Li Jia,et al.Effects of gradient structure on the microstructure and properties of coated cemented carbides.Journal of University of Science and Technology Beijing,2006,13(4):363-367
[4]Jose G,Reinhard P.The role of cemented carbide functionally graded outer-layers on the wear performance of coated cutting tools.Int.Journal of Refractory Metals and Hard Materials,2013,36:52-59
[5]Konigshofer R,Eder A,Lengauer W,et al.Growth of the graded zone and its impact on cutting performance in high-pressure nitrogen modified functionally gradient hardmetals.Journal of Alloys and Compounds,2004,336(1/2):228-332
[6]张武装,刘咏,贺跃辉,等.Ti(C,N)含量对硬质合金梯度结构和性能的影响.稀有金属与硬质合金,2005,33(2):28-30
[7]温光华,贺跃辉,王社权,等.Ti(C,N)的碳氮比及粒度对脱β层梯度硬质合金的影响.硬质合金,2009,20(4):201-205
[8]Xiong J,Guo Z X,Yang M,et al.Effect of ultra-fine Ti C0.5N0.5on the microstructure and properties of gradient cemented carbide.Journal of Materials Processing Technology,2009,209(12):5293-5299
[9]Ekroth M,Frykholm R,Lindholm M,et al.Gradient zones in WCTi(C,N)-Co-based cemented carbides-experiment study and computer simulations.Acta Materials.2000,48(9):2177-2185
[10]Frykholm R,Ekroth M,Jansson B,et al.A new labyrinth factor for modelling the effect of binder volμme fraction on gradient sinteing of cemented carbides.Acta Materials,2003,51:1115-1121
[11]Frykholm R,Jansson B,Andren H O.The influnce of carbon content on formation of carbo-nitride free surface layers in cemented carbides.International Journal of Refractory Metals and Hard Mateials,2002,20(5):345-353
[12]Frykholm R,Ekroth M,Jansson B,et al.Effect of cubic phase compositon on gradient zone formation in cemented carbides.International Journal of Refractory Metals and Hard Mateials,2001,19(4):527-538
[13]史留勇,刘义敏,张守全,等.脱β层梯度硬质合金的制备及组织结构.粉末冶金材料科学与工程,2011,16(1):67-72
[14]Roebuck B,Bennette G,Gee M G.Grain size mea-surement methods for WC/Co hardmetals.In:Bildstein H,Eck R.editors.Proc 13th Int Plansee seminar,Metallwerk Plansee,Reutte,1993,2:273-292
[15]Shetty D K,Wright P N,Glauer A H.Indentation fracture of WCCo cerments.Journal of Materials Science,1985:20(5):1873-1882
[16]Schwarzkopf M,Exner H E,Fischmeister H F.Kinetics of compositional modification of(W,Ti)C-WC-Co alloy surfaces.Materials science and engineering A,1988,105/106:225-231
[17]Ashe N G,Neethling J H,Berndt P R et al.A comparison of the microstructures of WC-VC-Ti C-Co and WC-VC-Co cemented carbides.International Journal of Refractory Metals and Hard Mateials,2007,25(3):207-213
[18]Weidow J,Zachrisson J,Jansson B et al.Characterization of WCCo with cubic carbide additions.International Journal of Refractory Metals and Hard Mateials,2009,27(2):244-248
[19]李勇,龙坚战.WC-Co硬质合金磁性能与晶粒度之间的关系.硬质合金,2010,27(4):195-198
[20]吴悦梅,熊计,赖人铭.碳含量对WC-Co硬质合金的显微组织的影响及其控制.硬质合金,2008,25(3):179-185
[21]刘昌斌,夏长清,李艳鑫.脱β层厚度对CVD涂层硬质合金性能的影响.硬质合金,2011,28(2):83-87