A high-strength Mg-15.3Gd-l.8Ag-0.3Zr （GQ152K, mass fraction） alloy was prepared by conventional ingot metallurgy process. The solution and aging （denoted as T6） treated alloy exhibits remarkable mechanical proper...A high-strength Mg-15.3Gd-l.8Ag-0.3Zr （GQ152K, mass fraction） alloy was prepared by conventional ingot metallurgy process. The solution and aging （denoted as T6） treated alloy exhibits remarkable mechanical properties with ultimate tensile strength of 421 MPa and tensile yield strength of 309 MPa. It has higher igniting temperature of 1 208 K. Moreover, it can stand against flame at 1 203 K for over 6 min in vertical burning tests, and its flammability behavior is very similar to that of 6101A1 alloy. Vertical burning tests appear to be able to directly study the flammability behavior of Mg alloys and it appears to be a good approach to study the flammability behavior of Mg alloys in an aircraft fire accident.展开更多
In this research, the flame retardancy of neat alginate fiber, flame retardant viscose fiber （FRV） and alginate/FRV （50/50） blending fibers were investigated by vertical burning and cone calorimeter tests. The ver...In this research, the flame retardancy of neat alginate fiber, flame retardant viscose fiber （FRV） and alginate/FRV （50/50） blending fibers were investigated by vertical burning and cone calorimeter tests. The vertical burning test showed that the afterflame time of alginate fiber was 0 s, but alginate presented serious smoldering behavior with the afterglow time of 605 s and damaged length of 85 mm, while the afterglow time of FRV was 0 s. When the FRV was incorporated into alginate with the weight ratio of 50/ 50, the afterglow time and damaged length were significantly reduced to 85 s and 35 mm, indicating the smoldering of alginate can be effectively decreased. The morphology and chemical structure of the alginate residual demonstrated that it was seriously destroyed during smoldering process, which was ascribed to its relative low initial thermal degradation temperature. Based on the thermal properties analysis, alginate and FRV fibers shared the concurrence of rapid degradation in the same temperature region of 250-300 ℃, through which, the compact and stable char formed by FRV can prevent the heat transmission and suppress the smoldering of alginate. Further, the cone calorimeter results demonstrated that the time to ignition （TTI） significantly increased and peak heat release rate （PHRR） decreased for alginate/FRV （50/50） compared with FRV. With this research, a new method to overcome the smoldering of alginate was proposed by blending with FRV展开更多
基金the National Natural Science Foundation of China(No.50971089)the China Postdoctoral Science Foundation(No.2012M511089)+2 种基金the China Postdoctoral Science Special Foundation (No.201003267)the Specialized Research Fund for the Doctoral Program of Higher Education (No.20110073120008)the Shanghai Phospherus Program Project(No.11QH1401200)
文摘A high-strength Mg-15.3Gd-l.8Ag-0.3Zr （GQ152K, mass fraction） alloy was prepared by conventional ingot metallurgy process. The solution and aging （denoted as T6） treated alloy exhibits remarkable mechanical properties with ultimate tensile strength of 421 MPa and tensile yield strength of 309 MPa. It has higher igniting temperature of 1 208 K. Moreover, it can stand against flame at 1 203 K for over 6 min in vertical burning tests, and its flammability behavior is very similar to that of 6101A1 alloy. Vertical burning tests appear to be able to directly study the flammability behavior of Mg alloys and it appears to be a good approach to study the flammability behavior of Mg alloys in an aircraft fire accident.
基金supported by the Fundamental Research Funds for the Central Universities(No. CUSF-DH-D2016012)
文摘In this research, the flame retardancy of neat alginate fiber, flame retardant viscose fiber （FRV） and alginate/FRV （50/50） blending fibers were investigated by vertical burning and cone calorimeter tests. The vertical burning test showed that the afterflame time of alginate fiber was 0 s, but alginate presented serious smoldering behavior with the afterglow time of 605 s and damaged length of 85 mm, while the afterglow time of FRV was 0 s. When the FRV was incorporated into alginate with the weight ratio of 50/ 50, the afterglow time and damaged length were significantly reduced to 85 s and 35 mm, indicating the smoldering of alginate can be effectively decreased. The morphology and chemical structure of the alginate residual demonstrated that it was seriously destroyed during smoldering process, which was ascribed to its relative low initial thermal degradation temperature. Based on the thermal properties analysis, alginate and FRV fibers shared the concurrence of rapid degradation in the same temperature region of 250-300 ℃, through which, the compact and stable char formed by FRV can prevent the heat transmission and suppress the smoldering of alginate. Further, the cone calorimeter results demonstrated that the time to ignition （TTI） significantly increased and peak heat release rate （PHRR） decreased for alginate/FRV （50/50） compared with FRV. With this research, a new method to overcome the smoldering of alginate was proposed by blending with FRV
