Typical Data   STANDARD ASTM C 155 GRADES
Properties   BNZ-20 BNZ-23 BNZ-23 HS BNZ-23A BNZ-26 BNZ-26-60 BNZ-28 BNZ-3000 BNZ-32
ASTM Classification   20/23 23 23 23 26 26 28 30 32
Temperature Use Limit
    (Normal oxidizing atmosphere)
°F
°
C
2300
1260
2300
1260
2300
1260
2300
1260
2600
1427
2600
1427
2800
1538
3000
1649
3200
1760
Density, Avg.
    ASTM C 134
lb/ft²
kg/m³
lb/BEq
kg/str.
36
577
2.1
0.9
37
593
2.2
1.0
42
673
2.5
1.1
33
529
1.93
0.86
48
769
2.8
1.3
50
801
2.9
1.3
55
881
3.2
1.5
65
1041
3.8
1.7
75
1201
4.4
2.0
Modulus of Rupture
    ASTM C 133
lb/in²
MPa
kg/cm²
95
0.7
6.7
105
0.7
7.4
140
1.0
9.9
115
0.79
8
200
1.4
14.1
190
1.3
13.4
220
1.5
15.5
250
1.7
17.6
300
2.1
21.1
Cold Crushing of Strength
    ASTM C 133
lb/in²
MPa
kg/cm²
105
0.7
7.4
125
0.9
8.8
190
1.3
13.4
145
1
10.2
270
1.9
19.0
290
2.0
20.4
340
2.3
23.9
440
3.0
31.0
450
3.1
31.7
Permanent Linear Change %                  
    ASTM C 210                    
    24 hrs at soaking temp: °F (°C)                    
    2250 (1232)   0.0 0.0 0.0 0.0
    2350 (1290)    
    2450 (1343)    
    2550 (1399)     -0.4 -0.2
    2750 (1510)     -0.7
    2800 (1538)    
    2950 (1621)     -0.7
    3150 (1732)     -0.4
Reversible Linear Thermal Expansion %                  
    at 2000°F (1093°C)   0.6 0.6 0.6 0.6 0.6 0.6 0.65 0.65 0.65
Hot Load Strength %                  
    ASTM C 16 deformation                  
    10 psi load for 11/2 hours: °F (°C)                    
    2000 (1093)   0 0 0 0
    2200 (1204)     0.2 0.1 0.1
    2400 (1316)     0.3 0.2
Thermal Conductivity Btu-in/ft², hr, °F                  
    ASTM C 182 (W/mk)                  
    Mean temperature, °F (°C)                    
      500   0.9 1.0 1.2 .92 1.6 1.8 2.3 2.8 3.9
      (260)   0.13 0.14 0.17 0.13 0.23 0.26 0.33 0.40 0.56
      1000   1.2 1.3 1.5 1.14 1.9 2.0 2.4 2.9 4.1
      (538)   0.17 0.19 0.22 0.16 0.27 0.29 0.35 0.42 0.59
      1500   1.5 1.6 1.7 1.39 2.2 2.1 2.6 3.1 4.2
      (816)   0.22 0.23 0.25 0.2 0.32 0.30 0.37 0.45 0.61
      2000   1.7 1.8 2.0 1.64 2.6 2.3 2.7 3.3 4.3
      (1093)   0.24 0.26 0.29 0.24 0.37 0.33 0.39 0.48 0.62
     To convert Btu-in/ft², hr,
°F to Kcal-m², hr,
°C,
     multiply by 0.124.
                   
Chemical Analysis                    
    Alumina – Al2O3   39.4 39.4 39.4 38 47.0 60.4 67.0 69.9 78.3
    Silica – SiO2   51.7 51.7 51.7 45 49.2 36.1 30.5 28.1 20.7
    Ferric Oxide – Fe2O3   0.6 0.6 0.6 0.3 0.6 0.4 0.3 0.3 0.2
    Titanium Oxide – Ti2O2   1.5 1.5 1.5 1.6 1.3 1.0 0.9 1.2 0.5
    Calcium Oxide – CaO   6.4 6.4 6.4 15 0.3 0.1 0.3 0.2 0.1
    Magnesium Oxide – MgO   0.1 0.1 0.1 0.1 0.1 0.2 0.0 0.1 0.1
    Alkalies, as Na2O & K2O   0.3 0.3 0.3 0.5 1.5 1.8 1.0 0.2 0.1