| SHS is a new technology which makes use of the high chemical reaction quantity ofheat produced between the reactants, and synthetic required materials in short time. Ithas been extensively applied because of its advantage that traditional coating processcannot liken. Based on the analysis of the thermodynamics, dynamics, burningmechanism, advantages and applications of SHS such as the literature, applying SHStechnology to coating-lined pipe, using SHS gravitational separation process,successfully prepared the thermal barrier coating which is thermal-resisting and lowfriction coefficient as well as corrosion-resisting.Produces the ceramic-lined composite pipes uses gravitational separation SHStechnology, deposit Ceramic coatings of TiC and Al2O3into steel pipe wall. Theorganization of ceramic-lined coating was investigated through optical microscopy,X-ray diffraction analysis, SEM morphology analysis and EDS energy spectrumanalysis methods, Its density, thermal shock resistance, corrosion resistance and otherperformance was studied. Changing the diameter, stuffing density as well as kind andcontent of additives, and study the effect to structure and properties of coating, thetheoretical analysis of thermal barrier coating was studied at last. The main results areas follows:（1） Using SHS gravitational separation process, successfully prepared the thermalbarrier coating which is thermal-resisting and wear-resisting as well ascorrosion-resisting. Because the two-phase of Fe and Al2O3which in reaction liquidseparated incompletely, Fe formed the transition layer between steel substrate andceramic layer, and the interface bonding is good. The holes and Fe particles existing inceramic layer decreased with the decrease of SiO2.（2） The main phase of coating is Al2O3, and it also contains much FeA12O4phase.The additives don’t change the main phase composition, however when MgO was addedwith right amount, the FeA12O4phase disappeared and the main phase is Al2O3.（3） When the stuffing density increased, the thickness increased and porositydecreased. When the pipe diameter increased, the hardness also increased. When thefilling density is1.5g/cm3, the porosity of ceramic layer is minimum of9.0%, and thethickness is biggest which is1.6mm. When the pipe diameter is25cm, the thickness isbiggest which is1917HV. （4） The hardness of coating was significantly higher than the base material, all of itcan reach more than1100HV. When the content of SiO2increased and the content ofCrO3decreased, the thickness of ceramic layer increased, at the same time, the porosityfirst decreased and then increased,however the density is just the opposite which firstincreased and then decreased.When adding2%SiO2+6%CrO3, porosity of coating isminimum and hardness is greatest; When adding Al2O3、ZnO、TiO2、MgO the hardnessof coating is also very high, which is highest and can reach1490HV of TiO2additive.（5） Results of thermal shock experimental shows that the thermal shock resistanceis the best when adding2%SiO2. Results of corrosion weightlessness experiment showcorrosion resistance is best when adding4%SiO2+4%CrO3, XRD analysis shows thatthe mainly phase reactded in the process of corrosion weightlessness experiment isFeA12O4and Mg2SiO4.（6） The main phase of Al2O3/TiC coating is Al2O3and TiC, it also has much AlNiphase and Cr phase when adds Ni. Al2O3/TiC coating has high hardness and the highdensity. The sample which adding Ni has higher density and hardness and thermalshock resistance also be improved, but the corrosion weightlessness rate increases.（7）The friction and wear experiment shows that compared with steel the coatingshave lower friction coefficient, proving that they have low friction coefficientperformance. Reference to the model of one-dimensional steady-state thermalconduction in a pipe, theoretical analysis and calculate the insulation effect of thethermal barrier coating, the results showed that the heat insulation temperature ofthermal barrier coating is532K, it has good heat insulation effects. |
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