Composite materials and devices comprising single crystal silicon carbide heated by electromagnetic radiation

Abstract

A composite material that increases in temperature upon exposure to electromagnetic radiation comprising single crystal silicon carbide whiskers and fibrils in a matrix material. Also, heat-generating objects comprising the composite material, and a method of generating heat.

1 . A composite material that increases in temperature upon exposure to electromagnetic radiation, said composite material comprising single crystal silicon carbide whiskers, fibrils, or a blend thereof, in a matrix material.  
   
   
       2 . The composite material of  claim 1  wherein the composite material comprises single crystal silicon carbide whiskers having a diameter between about 0.2 and about 10 microns and an aspect ration of between about 10 and 25.  
   
   
       3 . The composite material of  claim 1  wherein the composite material comprises silicon carbide fibrils having a diameter between about 4 and about 20 microns and a length of at least about 50 microns.  
   
   
       4 . The composite material of  claim 1  wherein the single crystal silicon carbide whiskers and fibrils further comprise a dopant.  
   
   
       5 . The composite material of  claim 4  wherein the dopant is nitrogen.  
   
   
       6 . A heat-generating object comprising a composite material that increases in temperature upon exposure to electromagnetic radiation, said composite material comprising single crystal silicon carbide whiskers, fibrils, or a blend thereof, in a matrix material.  
   
   
       7 . The object of  claim 6  wherein the composite material comprises single crystal silicon carbide whiskers having a diameter between about 0.2 and about 10 microns and an aspect ration of between about 10 and 100.  
   
   
       8 . The object of  claim 6  wherein the composite material comprises single crystal silicon carbide fibrils having a diameter between about 4 and about 20 microns and a length of at least about 50 microns.  
   
   
       9 . The object of  claim 6  wherein the single crystal silicon carbide whiskers and fibrils further comprise a dopant.  
   
   
       10 . The object of  claim 9  wherein the dopant is nitrogen.  
   
   
       11 . A microwave absorbing and heatable food processing article comprising composite material of  claim 1 .  
   
   
       12 . The article of  claim 11  wherein the article browns food contained therein when the article is exposed to microwave radiation.  
   
   
       13 . A method for generating heat comprising exposing a composite material that increases in temperature upon exposure to electromagnetic radiation comprising single crystal silicon carbide whiskers, fibrils, or a blend thereof, in a matrix material to electromagnetic radiation to heat it, and irradiating heat from the heated composite material.  
   
   
       14 . The method of  claim 13  wherein an object to be heated is placed in proximity of the composite material and is simultaneously exposed to the electromagnetic radiation.  
   
   
       15 . The method of  claim 13  wherein an object to be heated is not exposed to the electromagnetic radiation and is heated by heat transferred from the composite material after the composite material is heated by electromagnetic radiation.  
   
   
       16 . The method of  claim 13  wherein the heat is transferred from the heated component material by conduction, convection, or re-radiation of infrared radiation.  
   
   
       17 . The method of  claim 15  wherein the heat is transferred from the heated component material by conduction, convection, or re-radiation of infrared radiation.  
   
   
       18 . The method of  claim 13  wherein the composite material comprises single crystal silicon carbide whiskers having a diameter between about 0.2 and about 10 microns and an aspect ration of between about 10 and 100.  
   
   
       19 . The method of  claim 13  wherein the composite material comprises single crystal silicon carbide fibrils having a diameter between about 4 and about 20 microns and a length of at least about 50 microns.  
   
   
       20 . The method of  claim 13  wherein the single crystal silicon carbide whiskers and fibrils of the invention further comprise nitrogen dopant.  
   
   
       21 . A combination oven for heating with both microwaves and by convection, conduction, or infrared radiation from a heating element that absorbs microwave energy and radiates heat, wherein the heating element comprises composite material of  claim 1 .  
   
   
       22 . An insulated vessel comprising composite material of  claim 1  that effects heating inside a radiowave or microwave oven when the vessel is exposed to radiowave or microwave energy.  
   
   
       23 . A drying apparatus comprising composite material of  claim 1 .  
   
   
       24 . An apparatus for melting and fusing metals, said apparatus comprising composite material of  claim 1.