The Research On Structure Design And High Temperature Properties Of Heat-Resistant Skid Rail In Heating Furnace

As furnace heat-resistant skid rail, whole-heat skid rail with holes which design reasonable had been chosen to alternate traditional hot slide rails in this paper. Through atmospheric smelting, composition control of ZG4Cr28Ni48W5Si2Re and ZG4Cr25Ni20Si2NRe were stability, they can take place of Co-50 and Co-20 Mechanical property at elevated temperature and microscopic structure had been observed mainly on ZG4Cr25Ni20Si2NRe.This article analyzed variable regulars of mechanical property index of strength and plasticity with temperature by tensile test of ZG4Cr25Ni20Si2NRe at room-temperature, 650℃,750℃and 850℃.The curve of S-N was plotted by fatigue tests at 650℃and the fatigue limit 200MPa was obtained. Microscopic structure of dislocation and carbide under different service conditions were observed by metallographic microscope and TEM. The results showed that carbide and dislocation appeared obvious variation after tension at different temperatures. Carbide shape of material of fatigue tests at 650℃existed variation. In addition, fracture had been observed by SEM, analysis showed that all fractures had typical gliding fracture character, but fracture at room-temperature was flatter than fracture at elevated temperature; Fracture after fatigue had obvious three regions, source region of fatigue and crack propagation area belonged to brittle fracture, intermittent disconnection belonged to gliding fracture. Content of alloying agent of matrix and eutectic carbide of original sample and after service were measured by energy spectrometer. It showed that the content of alloying agent between matrix and carbide had obvious difference from carbide and carbide, and it was inferred that original eutectic carbide wasCr₇C₃.The corrosion resistance of Ni-base superalloy and Co-base superalloy at elevated temperature were observed through crucible tests. For Ni-base superalloy, the corrosion resistance at elevated temperature was obvious developed when percentages of Ni and Cr increased. The corrosion resistance of ZG4Cr25Ni20Si2NRe is equivalent to Co-20.