Fabrication and mechanical properties of porous TiB2 ceramic

Fracture toughness of porous materials – Experimental methods and data

“…Hong et al. [9]: After appropriate preparation, TiB 2 powder with a mean particle size of 2 μm was prepressed under uniaxial pressure and further compacted by (cold) isostatic pressing. Two different material variants were obtained by using 10 MPa and 50 MPa isostatic pressure.…”

“…The main data are the normalized fracture toughness and corresponding errors (if available in the references) as a function of the normalized porosity. These data are carefully extracted graphically from figures in the given references [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13], [14], [15], [16], [17]. Errors of a few percent like 1%–5% are possible, but they should be mostly below 2%.…”

“…[8]RBAO, uniaxial and cold isostatic pressingSEVNB, 4-point bending, notch tip radius 10 μm0.1 … 6 (grain size)Hong et al. [9]TiB 2 , uniaxial and cold isostatic pressing (10 and 50 MPa), sintering in vacuumSENB, 3-point bending, relative notch depth 0.5, average of 3 tests2 (particle size of powder)Samborski and Sadowski [10]Al 2 O 3 , (powder sintering technique)SEVNB, 3-point bending, relative notch depth 0.175–0.325–Maiti et al. [11]Foamed polymethacrylimid, (Rohacell, Rohm GmbH, Germany)SEVNB, 3-point bending, relative notch depth 0.5∼300 (for each porosity)McIntyre et al.…”

“…In four cases, only the absolute K IC -values were given. So, these data were normalized by dividing them by K IC (dense) of 5.44 [5], 4.16 [8], 3.21/4.18 [9], and 3.63 MPa√m [10], respectively. The latter numbers were obtained by extrapolation as described in Ref.…”

Improvement in the Specific Strength by Arranging Closed Pores in Fully Densified Zirconia Ceramics

“…High-strength porous ceramics have been produced by introducing pores into a matrix previously strengthened using some nonlinear toughening method such as fiber reinforcement or transformation toughening. [15][16][17][18][19] As a result, the toughened porous ceramics have a greater mechanical strength than a nontoughened dense ceramic, but a smaller strength compared to a toughened dense one.…”