In this study,three kinds of A380/Al2O3 composite coatings were prepared by cold spray(CS)using spherical,irregular and spherical+irregular shaped Al2O3 particulates separately mixed in the original A380 alloy powders...In this study,three kinds of A380/Al2O3 composite coatings were prepared by cold spray(CS)using spherical,irregular and spherical+irregular shaped Al2O3 particulates separately mixed in the original A380 alloy powders.The influence of Al2O3 particulates’morphology on the microstructural characteristics(i.e.retention of Al2O3 content in coatings,coating/matrix interfacial bonding,pore size distribution and morphology etc.)and wear performance of the coatings was investigated by scanning electron microscopy(SEM),X-ray computed tomography(XCT)and 3-D optical profilometry.Results indicated that the spherical Al2O3 showsobvious tamping effect during deposition process.As a result,the interfaceshowedawavy shape while the matrix and particulates were mechanical interlocked with much improved adhesion.In addition,the porosity of the coating was minimized and the pores exhibited curved spherical structure with reduced dimensions.The irregular Al2O3 particles predominantly displayed the embedding effect together with fragmentation of Al2O3 particulates.Consequently,poor coating/matrix interfacial bonding,high porosity and the formation of angular-shaped pores were resulted in the coating.Dry sliding wear tests results revealed that the wear resistance of the coating is directly related with the retained content of Al2O3 in the coating.The coating containing irregular Al2O3 particulates displayed superior wear performance with its wear rate one seventh of that of the pure A380 alloy coating.The coating containing both kinds of Al2O3 particulates showed mixed characteristics of above two kinds of Al2O3 composite coatings.展开更多
In this study,alumina/A380 composite coatings were fabricated by cold spray.The influence of alumina particulates,morphology(spherical and irregular)and content on the deposition behavior of the coatings(including sur...In this study,alumina/A380 composite coatings were fabricated by cold spray.The influence of alumina particulates,morphology(spherical and irregular)and content on the deposition behavior of the coatings(including surface roughness,surface residual stress,cross-sectional microstructure and microhardness)was investigated.Results revealed that the spherical alumina mainly shows micro-tamping effect during deposition,which result in remarkable low surface roughness and porosity of the coatings.In addition,very low deposition efficiency and good interfacial bonding between the coating and the substrate were achieved.For irregular alumina particles,the embedding of ceramic particulates in the coating was dominant during deposition process,resulting in high retention in the final deposit.However,it showed limited influence on porosity,surface roughness and interfacial bonding of the deposit.The coatings containing irregular alumina particulates exhibited much higher microhardness than those containing spherical alumina due to the higher load-bearing capacity of deposited alumina.展开更多
Cold spray(CS) is considered as a new type of repairing technique for restoration or remanufacturing of a wide range of unserviceable engineering components due to its unique ‘cold’ characteristic. In this work, a v...Cold spray(CS) is considered as a new type of repairing technique for restoration or remanufacturing of a wide range of unserviceable engineering components due to its unique ‘cold’ characteristic. In this work, a viable repairing approach i.e. "cold spraying followed by hot rolling post-treatment" was successfully applied to restore defective neutron shielding B_(4)C/6061 Al composite plates. Scanning electron microscopy(SEM) and electron backscatter diffraction(EBSD) results revealed that the coating-substrate interface is in a good bonding state without micro-cracks. Hot rolling post-treatment resulted in improved microstructure of the as-sprayed deposit with more uniform distribution of B_(4)C particles in the matrix.Moreover, well bonded splat boundaries and strain free Al grains were evolved in the matrix due to enhanced splat deformation and continuous dynamic recrystallization(CDRX). Three-point bending test results revealed that the strength of the repaired material is at par with the in-service plates. The findings of this work could be considered as a great stride to further extend possible applications of CS for repairing engineering structural components.展开更多
In our recently published article,“Influence of particulate morphology on microstructure and tribological properties of cold sprayed A380/Al_(2)O_(3) composite coatings”[Journal of Materials Science&Technology 4...In our recently published article,“Influence of particulate morphology on microstructure and tribological properties of cold sprayed A380/Al_(2)O_(3) composite coatings”[Journal of Materials Science&Technology 44(2020)9-18]”,Fig.5 got repeated inadvertently.This led to the displacement in the order of Figs.6 and 7 one step ahead.Consequently,the captions in Figs.6-8 in the manuscript were mismatched.Further,it caused the omission of Fig.8 described in the original manuscript.This erratum corrects the order of Figs.6-8 along with their corresponding figure captions.This erratum does not affect the conclusions of that paper.The publisher would like to apologize for any inconvenience caused.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(Nos.51671205 and 51801217).
文摘In this study,three kinds of A380/Al2O3 composite coatings were prepared by cold spray(CS)using spherical,irregular and spherical+irregular shaped Al2O3 particulates separately mixed in the original A380 alloy powders.The influence of Al2O3 particulates’morphology on the microstructural characteristics(i.e.retention of Al2O3 content in coatings,coating/matrix interfacial bonding,pore size distribution and morphology etc.)and wear performance of the coatings was investigated by scanning electron microscopy(SEM),X-ray computed tomography(XCT)and 3-D optical profilometry.Results indicated that the spherical Al2O3 showsobvious tamping effect during deposition process.As a result,the interfaceshowedawavy shape while the matrix and particulates were mechanical interlocked with much improved adhesion.In addition,the porosity of the coating was minimized and the pores exhibited curved spherical structure with reduced dimensions.The irregular Al2O3 particles predominantly displayed the embedding effect together with fragmentation of Al2O3 particulates.Consequently,poor coating/matrix interfacial bonding,high porosity and the formation of angular-shaped pores were resulted in the coating.Dry sliding wear tests results revealed that the wear resistance of the coating is directly related with the retained content of Al2O3 in the coating.The coating containing irregular Al2O3 particulates displayed superior wear performance with its wear rate one seventh of that of the pure A380 alloy coating.The coating containing both kinds of Al2O3 particulates showed mixed characteristics of above two kinds of Al2O3 composite coatings.
基金financially supported by the National Natural Science Foundation of China (Nos.51671205 and 51801217)
文摘In this study,alumina/A380 composite coatings were fabricated by cold spray.The influence of alumina particulates,morphology(spherical and irregular)and content on the deposition behavior of the coatings(including surface roughness,surface residual stress,cross-sectional microstructure and microhardness)was investigated.Results revealed that the spherical alumina mainly shows micro-tamping effect during deposition,which result in remarkable low surface roughness and porosity of the coatings.In addition,very low deposition efficiency and good interfacial bonding between the coating and the substrate were achieved.For irregular alumina particles,the embedding of ceramic particulates in the coating was dominant during deposition process,resulting in high retention in the final deposit.However,it showed limited influence on porosity,surface roughness and interfacial bonding of the deposit.The coatings containing irregular alumina particulates exhibited much higher microhardness than those containing spherical alumina due to the higher load-bearing capacity of deposited alumina.
基金financially supported by the National Natural Science Foundation of China (Nos.51671205 and 51801217)。
文摘Cold spray(CS) is considered as a new type of repairing technique for restoration or remanufacturing of a wide range of unserviceable engineering components due to its unique ‘cold’ characteristic. In this work, a viable repairing approach i.e. "cold spraying followed by hot rolling post-treatment" was successfully applied to restore defective neutron shielding B_(4)C/6061 Al composite plates. Scanning electron microscopy(SEM) and electron backscatter diffraction(EBSD) results revealed that the coating-substrate interface is in a good bonding state without micro-cracks. Hot rolling post-treatment resulted in improved microstructure of the as-sprayed deposit with more uniform distribution of B_(4)C particles in the matrix.Moreover, well bonded splat boundaries and strain free Al grains were evolved in the matrix due to enhanced splat deformation and continuous dynamic recrystallization(CDRX). Three-point bending test results revealed that the strength of the repaired material is at par with the in-service plates. The findings of this work could be considered as a great stride to further extend possible applications of CS for repairing engineering structural components.
文摘In our recently published article,“Influence of particulate morphology on microstructure and tribological properties of cold sprayed A380/Al_(2)O_(3) composite coatings”[Journal of Materials Science&Technology 44(2020)9-18]”,Fig.5 got repeated inadvertently.This led to the displacement in the order of Figs.6 and 7 one step ahead.Consequently,the captions in Figs.6-8 in the manuscript were mismatched.Further,it caused the omission of Fig.8 described in the original manuscript.This erratum corrects the order of Figs.6-8 along with their corresponding figure captions.This erratum does not affect the conclusions of that paper.The publisher would like to apologize for any inconvenience caused.
