Continuous open-ended sintering furnace system

Abstract

An open-ended continuous sintering furnace and system including means for providing a countercurrent protective gas atmosphere through a portion of the furnace and system and a substantially contaminant-free exit atmosphere throughout the remainder of the system and a continuous conveyor means of substantially solid refractory metal with notched retaining walls. The countercurrent protective gas atmosphere is provided so as to purge volatilized impurities released from workpieces past non-sintered or partially sintered workpieces. Such a flow thereby helps to prevent contamination of more fully sintered workpieces as they are cooled and exit the system. The partial countercurrent protective gas atmosphere is accomplished by multiple gas ejection means for ejecting the protective gas or by multiple sintering chambers with gas ejection between the chambers. Use of a continuous refractory metal conveyor belt means reduces contamination from the belt means to workpieces and allows for higher sintering temperatures due to its high mechanical strength at these temperatures. The belt means also includes retaining walls to prevent workpieces from being displaced from the belt means prior to and during sintering and these retaining walls are notched at regular intervals to provide flexibility when passing over conveyor driving means.