4J29 tube 1.Specilizing in kovar material 2. Have ISO9001:2008, RoHs, ... , 4J29 ,4J29 kKovar specification:Plate, sheet, strip, rod, bar, wire, tube.1.Alloy grades and chemical composition consistent with the provisions ... a,10-6/ oC20-300 oC20-400 oC20-450 oCkovarIn hydrogen atmosphere heated to 900 ± 20 oC, insulation 1h, and then ... -800oCkovar5.95.35.15.36.27.89.210.2 4J29 tube