Sintering Ultrahigh Melting

About

Invention Summary: Bulk and composite structural ceramics can be fabricated by sintering, forming particulate matter into a desired shape and then subjecting the formed body to high temperatures (2/3  of the melting temperature) and high pressures (250 MPa). These fabrication conditions are costly and lead to decomposition of non-oxide ceramics. Researchers at Rutgers have devised a method of sintering ultrahigh melting temperature covalent non-oxide ceramics at low temperatures. This sintering method exploits the conductivity of these ceramics by applying an electric field alongside heat. In addition to reducing costs by lowering the required temperature, this method can be accomplished at atmospheric pressure. The method can produce sub-100 nm grain size polycrystalline nonoxide ceramics with greater than 95% density. These ceramics are produced under better chemical and microstructural control, with high fracture strength, yet low overall fabrication cost. The new technology also has the potential of continuous manufacturing and is much faster even as a batch manufacturing system.   Market Application: •  Ceramic Manufacturing •  Automotive Specialty Products •  Aerospace and Defense Products •  Gas Turbines •  Tooling and Die Manufacture •  Protective Coatings •  High Friction Applications •  Nuclear Waste Management   Advantages: •  Avoid decomposition of non-oxide ceramics (B4C, ZrB2, TiB2, Si3N4, SiC, BN) •  Low temperature (2/9  melting, <1000 °C) •  Small grain size (<100 nm) •  High density (>95%) •  Rapid processing (<5 minutes) •  Atmospheric pressure •  Scalable with modest capital investment