D Jianxin et al/Int. Journal of Refractory Metals E Hard Materials 27(2009)734-739 [2 Cai Pz, Green D], Messing GL I al characterization of Al2O3/Zro, hybrid minates. J Eur Ceram Soc 1998 5: 2025-34. Al2O3/(Wo.7Tio.3)C+ Al2O3/TiC [3 de Portu G, Micele L Pezzotti G. Laminated ceramic structures from oxide with different thickness ratios amd [4] Sglavo Vincenzo M, Bertoldi Massimo. Design and production of ceramic duced by hot-pressing. Particular 二 laminates with high mechanical resistance and reliability. Acta Mater landri C, Pezzotti G, Sciti D. Effects of residual 1-oxide laminated composites. J Eur (1) Multilayered structure can induce excess residual [6 Tomaszewski Henryk ena, Wailer Anna, Boniecki Marek, Kalinski both at the entry and the exit due to the different ram Soc2007;27:1373-7 expansion coefficients of the individual layers. The [7 Sergo V, Lipkin DM, de Portu G, Clarke DR Edge stresses in alumina zirconia ual stresses are all compressive whatever the 03 3Y-TZP multilane (2)The hardness and fracture toughness at the external lay cence and Raman microprobe piezo-spectroscopy. Acta Mater 2005 entry or exit) decrease gradually from NI nozzle to N5 noz- 191 Tarla ncari E, Pinasco P, Guicciardi S. Melandri C, de portu G. le, and the nozzle with low thickness ratio shows the high- ibological behaviour of AlzO3ZrOx-Zroz laminated comp Wear (3) The layered nozzles(N1, N2, N3 and N4) had superior ero- [10/ ha:244: 29-40 est surface hardness and fracture toughness. G, Kubler]. Rosset e, Rohr L, Michler ]. Tribological l sion wear resistance to that of the stress-free one(n of Si3N4 and Si3Na-% Tin based composites and multi-layer laminates. Wear cially at the entry and the exit. The erosion wear resistance [11] Toschi F, Melandri C, Pinasco P, Roncari E, Guicciardi S, de PortuG.Influence of was influenced by the thickness ratio omposites. J Am Ceram Soc 2003: 86(9): 1547-53. imong constituent layers. The N4 nozzle with thickness [12\ e cerax Erosion wed composites. wear 20062650: 1 04-11 atio of two between adjacent layers exhibited higher ero- sion wear resistance over the ni n2 and n3 nozzles [13] Deng J 14Dengⅸ Feng YH, Dir ram Acknowledgement [15] Den t ceramIc for sand blasting surface treatments. Int J Refract Met Hard This work was supported by"the Lotus Scholars Programme "the Key Science and Technology Project of Shandong Province [16 Deng JX, Liu Ll Ding Mw. Effect e (2006GG2204017) 9:I-gn the erosion wear of [17 Deng X, Liu LL, Dir 1209 in dry sand esses. Mater Sci Eng A References [18] Deng JX, Liu LL, Zhao JL Sun JL Erosion wear of laminated ceramic nozzles. Int J [1] Lakshminarayanan R, Shetty DK, Cutler RA Toughening of layered ceramic efrat Met hard mat 79-87>Ites with residual surface compression. J Am Ceram Soc 9:19 ed indentation toughness technique. J Am Ceram Soc1983:66(11)200-14. Conclusions Al2O3/(W0.7Ti0.3)C + Al2O3/TiC multilayered ceramic nozzles with different thickness ratios among constituent layers were pro￾duced by hot-pressing. Particular attention was paid on wear behaviors of these nozzles. The following conclusions were obtained: (1) Multilayered structure can induce excess residual stresses both at the entry and the exit due to the different thermal expansion coefficients of the individual layers. These resid￾ual stresses are all compressive whatever the thickness ratios. (2) The hardness and fracture toughness at the external layer (entry or exit) decrease gradually from N1 nozzle to N5 noz￾zle, and the nozzle with low thickness ratio shows the high￾est surface hardness and fracture toughness. (3) The layered nozzles (N1, N2, N3 and N4) had superior ero￾sion wear resistance to that of the stress-free one (N5), espe￾cially at the entry and the exit. The erosion wear resistance of the layered nozzles was influenced by the thickness ratio among constituent layers. The N4 nozzle with thickness ratio of two between adjacent layers exhibited higher ero￾sion wear resistance over the N1, N2 and N3 nozzles. Acknowledgement This work was supported by ‘‘the Lotus Scholars Programme”, ‘‘the Key Science and Technology Project of Shandong Province (2006GG2204017)”. References [1] Lakshminarayanan R, Shetty DK, Cutler RA. Toughening of layered ceramic composites with residual surface compression. J Am Ceram Soc 1996;79(1): 79–87. [2] Cai PZ, Green DJ, Messing GL. Mechanical characterization of Al2O3/ZrO2 hybrid laminates. J Eur Ceram Soc 1998;5:2025–34. [3] de Portu G, Micele L, Pezzotti G. Laminated ceramic structures from oxide systems. Comp Part B 2006;37:556–67. [4] Sglavo Vincenzo M, Bertoldi Massimo. Design and production of ceramic laminates with high mechanical resistance and reliability. Acta Mater 2006;54:4929–37. [5] Guicciardi S, Nagliati M, Melandri C, Pezzotti G, Sciti D. Effects of residual stresses on the fracture properties of non-oxide laminated composites. J Eur Ceram Soc 2007;27:351–6. [6] Tomaszewski Henryk, Weglarz Helena, Wajler Anna, Boniecki Marek, Kalinski Dariusz. Multilayer ceramic composites with high failure resistance. J Eur Ceram Soc 2007;27:1373–7. [7] Sergo V, Lipkin DM, de Portu G, Clarke DR. Edge stresses in alumina/zirconia laminates. J Am Ceram Soc 1997;80(7):1633–8. [8] de Portu G, Micele L, Sekiguchi Y, Pezzotti G. Measurements of residual stress distributions in Al2O3/3Y–TZP multilayered composites by fluore￾scence and Raman microprobe piezo-spectroscopy. Acta Mater 2005;53: 1511–20. [9] Tarlazzi A, Roncari E, Pinasco P, Guicciardi S, Melandri C, de Portu G. Tribological behaviour of Al2O3/ZrO2–ZrO2 laminated composites. Wear 2000;244:29–40. [10] Hadad M, Blugan G, Kübler J, Rosset E, Rohr L, Michler J. Tribological behaviour of Si3N4 and Si3N4–% TiN based composites and multi-layer laminates. Wear 2006;260:634–41. [11] Toschi F, Melandri C, Pinasco P, Roncari E, Guicciardi S, de Portu G. Influence of residual stress on the wear behaviour of alumina/alumina–zirconia laminated composites. J Am Ceram Soc 2003;86(9):1547–53. [12] de Portu G, Micele L, Prandstraller D, Palombarini G, Pezzotti G. Abrasive wear in ceramic laminated composites. Wear 2006;260:1104–11. [13] Deng JX. Erosion wear of boron carbide nozzles by abrasive air-jets. Mater Sci Eng A 2005;408(1–2):227–33. [14] Deng JX, Feng YH, Ding ZL. Wear behaviors of the ceramic nozzles in sand blasting treatments. J Eur Ceram Soc 2003;23:323–9. [15] Deng JX, Liu LL, Li JF, Ding MW, Yang XF. Development of gradient ceramic nozzle materials for sand blasting surface treatments. Int J Refract Met Hard Mater 2007;25:130–7. [16] Deng JX, Liu LL, Ding MW. Effect of residual stresses on the erosion wear of laminated ceramic nozzles. Mater Charact 2008;59:1–8. [17] Deng JX, Liu LL, Ding MW. Erosion wear behaviours of SiC/(W, Ti)C laminated ceramic nozzles in dry sand blasting processes. Mater Sci Eng A 2007;444:120–9. [18] Deng JX, Liu LL, Zhao JL, Sun JL. Erosion wear of laminated ceramic nozzles. Int J Refract Met Hard Mater 2007;25:263–70. [19] Cook RF, Lawn BR. A modified indentation toughness technique. J Am Ceram Soc 1983;66(11):200–1. D. Jianxin et al. / Int. Journal of Refractory Metals & Hard Materials 27 (2009) 734–739 739