Abstract:
A NEW CERAMIC TREATMENT PROCESS ANDPRODUCT AND, MORE PARTICULARY, A PROCESS FOR TREATING UNDERFIRED POROUS PARTIALLY VITRIFIED RELATIVELY SOFT MACHINABLE REFRACTORY CERAMIC MATERIALS TO PRODUCE HARDENED DIMENSIONALLY STABLE END PRODUCTS AT RELATIVELY LOW TEMPERATURES AND THE CERAMIC MATERIALS PRODUCED THEREBY WHICH ARE SUITABLE FOR APPLICATION AS BEARINGS FOR UNDERSEA SUBMERGENCE, LOW TEMPERATURE BEARINGS FOR ARCTIC VEHICULAR AND MACHINERY APPLICATIONS, PRECISION BEARINGS FOR SPACE USE AND LIQUID METAL LUBRICATED SYSTEMS. THE SOFT CERAMICS CAN BE MACHINED AND SHAPED IN THE SOFT STATE AND HARDENED BY THE PROCESS OF THIS INVENTION AT TEMPERATURES WELL BELOW NORMAL VITRIFICATION TEMPERATURES WITH VIRTUALLY NO CHAGE IN DIMENSIONS FROM THE MACHINED UNTREATED CERAMIC TO THE TREATED AND HARDENED END PRODUCT. OTHER PRODUCTS PRODUCED BY THE PROCESS OF THIS INVENTION PRODUCE ARTICLES HAVING A VERY DENSE SURFACE CAPABLE OF TAKING A HIGH POLISH AND OTHER PRODUCTS HAVE RESULTED IN AN ABRASIVE OR POLISHING STONE HAVING SUPERIOR QUALITIES TO THOSE OF THE ARKANSAS STONES IN RESPECT TO BOTH SPEED OF METAL REMOVAL AND DEGREE OF POLISHING OR SHARPENING. IN ADDITION, COARSER OR FINER GRADES ARE OBTAINABLE COMPARED TO A SINGLE GRADE OF ARKANSAS STONE. OTHER PRODUCTS PRODUCED BY THIS PROCESS HAVE NEGATIVE TEMPERATURES COEFFICIENTS BECOMING VERY GOOD ELECTRICAL AND HEAT CONDUCTORS AT HIGH TEMPERATURES.
Abstract:
Sealed neutron generator containing an isotope of hydrogen having an ion source, an accelerator and a target containing a substance which reacts with impinging ions to produce neutrons maintained at ground potential and located to be available at the exterior of the generator.