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102.jpg (3709 bytes)  Dense Alumina Hearth Plate Type DAHP

GENERAL INFORMATIONplate.jpg (9002 bytes)
ZIRCAR Dense Alumina Hearth Plates are used for supporting loads in high temperature furnaces and other thermal process systems. These dense plates are made of fully sintered fine grain high purity alumina. Designed for use as high load bearing members, they exhibit high strength at operating temperatures as high as 3400F (1870C).

DAHP hearth plates are normally used as hearth plates in rapid cycle furnaces with air atmospheres operating to 3317F (1825C) . They may be positioned directly on the furnace floor or supported with hearth posts such as Reticulated Alumina Hearth Post Type RAHP.

These plates are also useful in furnaces with hydrogen atmospheres operating over  3100F (1700C). They are of exceptional high purity and contain only a trace of tramp oxides. 

Chemical Analysis, %
     Al2O2 99.55
     SiO2 0.07
     Fe2O3 0.09
     K2O & Na2O 0.25
     Other Oxides 0.04
Maximum use temperature, F (C) 3400 (1870)
Bulk Density, g/cc 3.2
Apparent Porosity, % 20
Modulus of Elasticity, GPa 85
Modulus of Rupture, psi
     Room Temperature     2800
     2280F (1250C) 1800
     2640F (1450C) 1000
Crushing Strength, Room Temperature, psi     11000
Linear Thermal Expansion, 30-1500C, C 8.4 x 10-6
Thermal Conductivity, BTU-in./hr.ft.2 (W/mK)
     2200F (1200C) 16.0 (2.3)
Specific Heat, BTU/lb.F .27
Total Emittance
     930F (500C) .42
     2010F (1100C) .28
     2732F (1500C) .38
Permeability Range, g/S.Pa.m) 35-70 x 10-6


Load bearing members in furnaces and thermal process systems operating as high as 3400F (1870C).

Hearth plates in rapid cycle furnaces with air atmospheres operating to 3317F (1825C).

Support plates in furnaces with hydrogen atmospheres operating over  3100F (1700C). 

High temperature setters, supports and process fixtures.

msds.jpg (1069 bytes)MATERIAL SAFETY DATA SHEETmsds.jpg (1069 bytes)





SHIP WT. (lb.)



 DAHP, 6in.W x 6in.L x 0.50in.T $117.00 5


 DAHP, 8in.W x 8in.L x 0.75in.T $150.50 6
 * Note: Prices shown apply to sales within the United States. Contact us for information regarding international commerce.

To place your order, please click the respective "ORDER" button next to the item you wish to purchase. To view your shopping cart click the button to the right. For more info -click here-


Standard hearth plates are available for immediate shipment from stock.

Allowable Warpage 3%.

Custom plates, tubes, muffles, kiln furniture, other shapes and preparations are available on request.

Variations such as Dense Alumina Hearth Plate Type DAHPB and DAHPC are available on a custom basis. These alternate grades differ from DAHP in that their alternate processing produces slightly different physical properties - making them better suited for some applications.

Modulus of Elasticity, GPa 75 90
Modulus of Rupture, psi
     Room Temperature  1800 3200
     2280F (1250C) 1400 2200
     2640F (1450C) 400 1200
Crushing Strength, Room Temperature, psi 8000 13000

Please contact us with your special requirements. We are pleased to contact you if you would like more information or want to discuss custom product availability and pricing.

To Order

Standard plates: order online or specify quantity, item # and description.

Custom plates: specify quantity and size. Example: 24ea, DAHP, 7.5in.W x 6in.L x .75in.T

Custom plates, shapes and preparations: specify quantity and description (by supplying drawings, sketches, written descriptions or material specifications).

Copyright 2001  ZIRCAR Ceramics, Inc.