Alumina bending strength

FIG. 205, The effect of grain size and temperature on bending strength of pure dense hot-pressed alumina (Spriggs et al., 1964). 

Table 8 Effect of porosity on the bend strength of polycrystalline alumina at 25°C from [2]...

Experimentally, many results have shown the fall in strength of a gel as porosity is increased. This is true of compressive strength, tensile, and bending strength. It is also true for a wide range of substances made by different methods natural rock and firebrick, alumina and zirconia, iron, cement, plaster of paris, and ice, as shown in Fig. 1120. A typical empirical expression used to describe the results is that due to Ryshkewitch and Duckworth, ... 

Bend strength (YSZ) Bend strength (Alumina) —0— Contact angle (YSZ) -O- Contact angle (Alumina) 1 1 ... 

Figure 11.5 Comparison of room-temperature four-point bend strength and contact angle between alumina and YSZ joints brazed at lOOO C using CuO-Ag braze [79].

Krause, R.F., 1988. Rising fracture toughness from bending strength of indented alumina beams. J. Am. Ceram. Soc. 71, 338. 

Table 1. Four point bending strength, fracture toughness measured by single edge pre cracked beam (SEPB) method, and Vickers hardness of the tested alumina specimens. Standard deviations are in brackets.

Fully dense fibers consisting of pure YAG phase were obtained by the 1600°C-heat-treatment of the gel fibers drawn from the solution of yttrium acetate hydrate/aluminum formate hydrate/H20/formic acid/ethylene glycol. The bending strength of the fibers was 1.7 0.2 GPa (Liu et al, 1998). Pullar et al. (1998a, 1999) also fabricated pure YAG fibers from aqueous sol-gel precursors. They blow-span the stoichiometric mixture of the alumina sol and silica sol by using PEO as a spinning aid. The HCl added to the sol as a peptizer was found to stabilize the sol, and to play important roles for the appearance of spinnability and also to improve the sinterability of the fibers. Fully dense YAG fibers obtained by them at 1600°C exhibited improved friability. 

Fignre 2-17 Flexnral Bending strength of glass/alumina --------------46... 

Bending strength and hardness of alumina/zirconia nano-composite ceramics are improved because the crystal size of the composite ceramics are smaller than alumina and zirconia ceramics. Hence it is unlikely that micro-ploughing... 

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