The functionally graded thermal barrier coatings （FG-TBCs） with 80%ZrO2-13%CeO2-7%Y2O3 （C-YSZ）/NiCoCrAlY were prepared using a recently developed supersonic plasma spraying（S-PS） with dual powder feed ports syst...The functionally graded thermal barrier coatings （FG-TBCs） with 80%ZrO2-13%CeO2-7%Y2O3 （C-YSZ）/NiCoCrAlY were prepared using a recently developed supersonic plasma spraying（S-PS） with dual powder feed ports system. The thermal shock experiment of FG-TBCs specimens was carried out by means of the automatic thermal cycle device, in which the samples were heated to 1200℃ by oxygen-acetylene flame jet then water-quenched to ambient temperature. The temperature—time curves of specimens and photographs can be watched on-line and recorded by a computer during the test. The results show that the totally 1mm-thick FG-TBCs have excellent thermal shock resistance due to the fact that the coatings have no any peeling-off after 200 thermal cycles. The microstructures and morphologies of FG-TBCs were characterized and analyzed by SEM.展开更多
The NiCrBSi/WC biomimetic coatings were prepared on the low carbon steel substrate by plasma spray welding with mixed powders （WC-Col2＋NiCrBSi） based on the bionic principles, and the coating characteristics were i...The NiCrBSi/WC biomimetic coatings were prepared on the low carbon steel substrate by plasma spray welding with mixed powders （WC-Col2＋NiCrBSi） based on the bionic principles, and the coating characteristics were investigated. The results indicate that the coatings have a full metallurgical bond in coating/substrate interface, and consist mainly ofy-Ni, WC, Cr23C6, Cr7C3, Ni3Si, CrsB3, and FeNi3 phases. The powder composition influences the microstructures and properties of the coatings. The WC content and the hardness of coatings increase with the mass fraction of WC-Co 12 powder. The biomimetic coatings have much higher wear resistance compared with the low carbon steel, which is attributed to the combination of hard WC and chromium carbide particles （bionic units） and soft y-Ni matrix in the coatings. It is favorable to prepare the biomimetic coating by plasma spray welding with the mixed powders （20wt%WC-Col2＋80wt%NiCrBSi） for improving the wear resis- tance of the coating.展开更多
Wall sticking,which greatly reduces productivity and product quality,has been a big challenge of spray drying.Structure of drying tower and atomizer,as well as drying conditions are the main influencing factors.This r...Wall sticking,which greatly reduces productivity and product quality,has been a big challenge of spray drying.Structure of drying tower and atomizer,as well as drying conditions are the main influencing factors.This research explored the possibility to reduce wall sticking by optimizing drying conditions and components to obtain higher recovery rate of powdered infant formula milk(PIFM).Response surface experimental results indicated that inlet air temperature(T),feed concentration(C),feeding speed(S),as well as interaction term of TC and quadratic terms of C^(2) and S^(2) had significant influences on recovery rate for determined milk formula.According to mixture experiments at optimized drying conditions,whey protein(P),fat(F)and lactose(L)contents,as well as interaction term FL had significant effects on recovery rate.Positive effects were observed for F and L contents on recovery rate,while negative effects were observed for P and FL.Under the optimized drying condition of 136℃,19.80%and 4.07 mL/min,respectively,for T,C and S,the maximum recovery rate of 58.98%was obtained for PIFM with P,F and L content of 18%,31%and 51%,respectively.Wall sticking phenomena could be reduced by optimizing drying conditions and mildly adjusting components of infant formula milk.展开更多
文摘The functionally graded thermal barrier coatings （FG-TBCs） with 80%ZrO2-13%CeO2-7%Y2O3 （C-YSZ）/NiCoCrAlY were prepared using a recently developed supersonic plasma spraying（S-PS） with dual powder feed ports system. The thermal shock experiment of FG-TBCs specimens was carried out by means of the automatic thermal cycle device, in which the samples were heated to 1200℃ by oxygen-acetylene flame jet then water-quenched to ambient temperature. The temperature—time curves of specimens and photographs can be watched on-line and recorded by a computer during the test. The results show that the totally 1mm-thick FG-TBCs have excellent thermal shock resistance due to the fact that the coatings have no any peeling-off after 200 thermal cycles. The microstructures and morphologies of FG-TBCs were characterized and analyzed by SEM.
文摘The NiCrBSi/WC biomimetic coatings were prepared on the low carbon steel substrate by plasma spray welding with mixed powders （WC-Col2＋NiCrBSi） based on the bionic principles, and the coating characteristics were investigated. The results indicate that the coatings have a full metallurgical bond in coating/substrate interface, and consist mainly ofy-Ni, WC, Cr23C6, Cr7C3, Ni3Si, CrsB3, and FeNi3 phases. The powder composition influences the microstructures and properties of the coatings. The WC content and the hardness of coatings increase with the mass fraction of WC-Co 12 powder. The biomimetic coatings have much higher wear resistance compared with the low carbon steel, which is attributed to the combination of hard WC and chromium carbide particles （bionic units） and soft y-Ni matrix in the coatings. It is favorable to prepare the biomimetic coating by plasma spray welding with the mixed powders （20wt%WC-Col2＋80wt%NiCrBSi） for improving the wear resis- tance of the coating.
基金supported by the National Natural Science Foundation of China(31301563)Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment&Technology(FM-2014).
文摘Wall sticking,which greatly reduces productivity and product quality,has been a big challenge of spray drying.Structure of drying tower and atomizer,as well as drying conditions are the main influencing factors.This research explored the possibility to reduce wall sticking by optimizing drying conditions and components to obtain higher recovery rate of powdered infant formula milk(PIFM).Response surface experimental results indicated that inlet air temperature(T),feed concentration(C),feeding speed(S),as well as interaction term of TC and quadratic terms of C^(2) and S^(2) had significant influences on recovery rate for determined milk formula.According to mixture experiments at optimized drying conditions,whey protein(P),fat(F)and lactose(L)contents,as well as interaction term FL had significant effects on recovery rate.Positive effects were observed for F and L contents on recovery rate,while negative effects were observed for P and FL.Under the optimized drying condition of 136℃,19.80%and 4.07 mL/min,respectively,for T,C and S,the maximum recovery rate of 58.98%was obtained for PIFM with P,F and L content of 18%,31%and 51%,respectively.Wall sticking phenomena could be reduced by optimizing drying conditions and mildly adjusting components of infant formula milk.
