L&L Special Furnace Co. Inc. shipped and installed a box retort furnace to a manufacturer of aerospace components located in the southern U.S. The furnace will be used to debinder ceramic-matrix-composite (CMC) parts. The main function of the furnace is to remove all organics and other materials used in the product prior to placing it in a high-fire vacuum chamber. This debindering process allows for a finished product that is not only very strong but also lightweight.
The furnace has a work zone measuring 9 inches wide x 9 inches high x 18 inches deep. It has a temperature gradient of ±20°F at 1100°F using six heating banks with biasing control to balance any temperature gradients. The furnace is controlled by a Eurotherm program control with over-temperature protection. There is also a programmable flow panel to manage nitrogen flow throughout the process.
The parts are heated to 1220°F in a retort chamber that is pressurized with nitrogen. The byproducts of the outgassing part are directed by pressure and flow out of the rear of the furnace. After debindering, the parts are heated in a vacuum furnace to temperatures in excess of 2300°F. The result is a super-strong component that is more resilient and lighter than titanium.