Currently,the working temperature of metal and ceramic materials used in infrared detectors is about 80K,so compared to common metal/ceramic soldering line,the soldering line in infrared detectors is different.In this paper,the current ceramic/metal brazing methods are reviewed,the experiment of the soldering process was carried out with a kind of solder based on AgCuTi metal.Direct soldering(non - metallization)of ceramic(sapphire)to kovar was realized.After the experiment,the inspection of weld porosity and temperature shock resistance test(333~77K)were carried out.The result showed that this kind of soldering method can meets the demand of soldering of ceramic(sapphire)to kovar of the infrared detectors.The soldering parts prepared by this method can be used in ultra-low temperature environment for a long time.