Fabrication of Graded Nickel–Alumina Composites with a Thermal-Behavior-Matching Process

Composites of nickel and Al2O3 with compositionally graded microstructures were fabricated from powders through an empirically determined thermal-behavior-matching process that was designed to minimize processing-induced stresses. Compositions ranged from pure Al2O3 to pure nickel. Specimen geometries included round disks 25 mm in diameter and 5–25 mm thick, as well as rectangular bars 25 mm × 25 mm in cross section and 75 mm long. Several different gradients were produced, including samples with single interlayers. Compacts were formed by cold uniaxial pressing in a die, followed by consolidation through sintering at 1 atm or hot isostatic pressing. Several different particle sizes of nickel and Al2O3 comprised the composite interlayers. The compaction behavior, sintering start temperature, sintering rate, and total linear shrinkage of each composition were evaluated. Careful data analysis, coupled with sintering theory, led to a layer configuration with matched green density and sintering behavior. Thermomechanically matched layers allowed large, crack-free, graded composites to be produced.

[1]  Hugh A. Bruck,et al.  Residual Strains in an Al2O3‐Ni Joint Bonded with a Composite Interlayer: Experimental Measurements and FEM Analyses , 2005 .

[2]  R. Chen,et al.  Pressureless Sintering of Al2O3/Ni Nanocomposites , 1999 .

[3]  J. Yeo,et al.  Design and microstructure of ZrO2/SUS316 functionally graded materials by tape casting , 1998 .

[4]  Yeon-Gil Jung,et al.  Fabrication of 3Y-TZP/SUS304 functionally graded materials by slip casting; application of porous alumina molds , 1998 .

[5]  Zou,et al.  STRESS INTENSITY FACTORS FOR A FUNCTIONALLY GRADED MATERIAL CYLINDER WITH AN EXTERNAL CIRCUMFERENTIAL CRACK , 1998 .

[6]  M. Gasik.  Micromechanical modelling of functionally graded materials , 1998 .

[7]  Huijuan Zhao,et al.  Optimization of 316 stainless steel/alumina functionally graded material for reduction of damage induced by thermal residual stresses , 1998 .

[8]  Yi-der Lee,et al.  Interface cracking of FGM coatings under steady-state heat flow , 1998 .

[9]  Christopher C. Berndt,et al.  Tensile toughness test and high temperature fracture analysis of thermal barrier coatings , 1997 .

[10]  S. Sampath,et al.  Erosion studies on duplex and graded ceramic overlay coatings , 1996 .

[11]  Zhongmin Jin,et al.  Some basic fracture mechanics concepts in functionally graded materials , 1996 .

[12]  F. Wakai,et al.  Fabrication of zirconia-alumina functionally gradient material by superplastic diffusion bonding , 1993, Journal of Materials Science.

[13]  Richard L. Williamson,et al.  Finite element analysis of thermal residual stresses at graded ceramic‐metal interfaces. Part I. Model description and geometrical effects , 1993 .

[14]  K. Trumble,et al.  The thermodynamics of spinel interphase formation at diffusion-bonded Ni/Al2O3 interfaces , 1991 .

[15]  S. Datta,et al.  Functionally graded ceramic/ceramic and metal/ceramic composites by electrophoretic deposition , 1997 .

[16]  Robert J. Asaro,et al.  Cracks in functionally graded materials , 1997 .

[17]  Zhu Jing-chuan,et al.  Fabrication and microstructure of ZrO2/NiCrCoAlY graded coating by plasma spraying , 1997 .

[18]  K. Morinaga,et al.  Al2O3/Y-TZP continuous functionally graded ceramics by filtration-sedimentation , 1997 .

[19]  R. Chen,et al.  Effect of sintering atmosphere on the mechanical properties of composites , 1997 .

[20]  R. Watanabe,et al.  Evaluation of thermomechanical performance for thermal barrier type of sintered functionally graded materials , 1997 .

[21]  D. Juvé,et al.  Nickel-alumina bonds: Mechanical properties related to interfacial chemistry , 1996 .

[22]  J. Yeomans,et al.  Microstructure and fracture toughness of nickel particle toughened alumina matrix composites , 1996, Journal of Materials Science.

[23]  Michael J. Hoffmann,et al.  Properties and interface structures of Ni and Ni-Ti alloy toughened Al2O3 ceramic composites , 1995 .

[24]  Richard L. Williamson,et al.  FEM study of the effects of interlayers and creep in reducing residual stresses and strains in ceramic-metal joints , 1995 .