Mechanical properties of porous PNZT polycrystalline ceramics

Conference · Mon Aug 01 04:00:00 EDT 1977

OSTI ID:5346574

Biswas, D R; Fulrath, R M

Niobium-doped lead zirconate-titanate (PNZT) was used to investigate the effect of porosity on the mechanical properties of a polycrystalline ceramic. Spherical pores (110 to 150 ..mu..m diameter) were introduced by using organic materials in the initial specimen fabrication. The matrix grain size (2 to 5 ..mu..m) was kept constant. Small pores (2 to 3 ..mu..m diameter) of the order of the grain size were formed by varying the sintering conditions. The effect of porosity on strength was predicted quite well by Weibull's probabilistic approach. The Young's modulus showed a linear relationship with increase in porosity. A decrease in fracture toughness with increase in porosity was also observed. It was found that at equivalent porosities, small pore specimens gave higher strength, Young's modulus and fracture toughness compared to specimens containing large pores. Fracture surface analysis, by scanning electron microscopy, showed fracture originated either at the tensile surface or at the edge of the specimen.

• Research Organization: California Univ., Berkeley (USA). Lawrence Berkeley Lab.
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 5346574
• Report Number(s): LBL-6683; CONF-770743-1
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360203* -- Ceramics
Cermets
& Refractories-- Mechanical Properties
ALLOYS
CERAMICS
ELASTICITY
FRACTURE PROPERTIES
LEAD COMPOUNDS
MECHANICAL PROPERTIES
NIOBIUM ADDITIONS
NIOBIUM ALLOYS
OXYGEN COMPOUNDS
POROSITY
SINTERED MATERIALS
TENSILE PROPERTIES
TITANATES
TITANIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
YOUNG MODULUS
ZIRCONATES
ZIRCONIUM COMPOUNDS