为降低紫外线对聚丙烯(Polyethylene,PP)非织造土工布的影响,选择ES(Ethylene-Propylene Side By Side)纤维和含有抗老化母粒的PP纤维为原料,TiO_(2)浸轧处理为后整理工序,采用针刺加固和热黏合加固技术制备了具有抗紫外老化功能的PP/E...为降低紫外线对聚丙烯(Polyethylene,PP)非织造土工布的影响,选择ES(Ethylene-Propylene Side By Side)纤维和含有抗老化母粒的PP纤维为原料,TiO_(2)浸轧处理为后整理工序,采用针刺加固和热黏合加固技术制备了具有抗紫外老化功能的PP/ES高强非织造土工布。研究了抗老化工艺对PP/ES土工布力学性能和抗紫外老化性能的影响。结果表明:添加抗老化母粒和TiO_(2)浸轧后整理的PP/ES土工布力学性能少许上升;该土工布紫外老化后的羰基吸收峰强度最弱,T 5%仅下降4.73℃,纵向和横向的断裂强度保留率仅下降26.55%和26.76%,表现出最佳的抗紫外老化性能。展开更多
The microstructural evolution and mechanical properties of a spray-formed superalloy were studied in this paper. Based on a better understanding of the microstructural evolution of the spray-formed superalloy during s...The microstructural evolution and mechanical properties of a spray-formed superalloy were studied in this paper. Based on a better understanding of the microstructural evolution of the spray-formed superalloy during solution treatment, an optimum solution treatment process was obtained, namely, at 1,140 °C for 6 h, and air cooling(AC). The effects of the ageing treatments on the mechanical properties of the post-solution-treated spray-formed superalloy were evaluated using ageing harden curves and tensile testing. The results indicated that the maximum hardness value was achieved at 850 °C for 8 h, AC. Due to co-precipitation of primary and secondary c0 precipitates during the heat treatment,the spray-formed superalloy obtained an excellent combination of yield strength(YS = 1,110 MPa), ultimate tensile strength(UTS = 1,503 MPa), ductility(elongation, EL = 21%) and excellent stress rupture properties at 650 °C(UTS = 1,209 MPa, EL = 15.8%). The heat treatment also improved the rupture life at 650 °C/950 MPa and 750 °C/539 MPa up to 140 h without rupturing. The tensile-fractured surfaces exhibit ductile transgranular failure feature. The optimum heat treatment process was determined to be 1,140 °C/6 h+850 °C/8 h+AC.展开更多
Cu-Ag-RE alloys with different Ce contents were prepared by vacuum melting, and microstructure evolution and mechanical properties of Cu-Ag-Ce alloys were investigated by optical microscopy, scanning electronic micros...Cu-Ag-RE alloys with different Ce contents were prepared by vacuum melting, and microstructure evolution and mechanical properties of Cu-Ag-Ce alloys were investigated by optical microscopy, scanning electronic microscopy with electron back-scattered diffraction and tensile test. The results indicated that a columnar to equiaxed transition in cast Cu-Ag-RE alloys was observed due to Ce addition and area of the region with equiaxed grains enlarged with increasing Ce content. Cold-rolled Cu-Ag-RE alloys in annealed condition exhibited a partially or fully recrystallized grain structure depending on the concentration of Ce. The average grain size decreased and texture components changed with increasing Ce content. The main brass-type texture component changed to be copper-type as the Ce content increased from 0.05 wt.% to 1.0 wt.%. The Cu-Ag-RE alloy with 0.2 wt.% Ce showed maximum ultimate tensile strength, while the sample with 1.0 wt.% Ce showed a better comprehensive mechanical property.展开更多
文摘为降低紫外线对聚丙烯(Polyethylene,PP)非织造土工布的影响,选择ES(Ethylene-Propylene Side By Side)纤维和含有抗老化母粒的PP纤维为原料,TiO_(2)浸轧处理为后整理工序,采用针刺加固和热黏合加固技术制备了具有抗紫外老化功能的PP/ES高强非织造土工布。研究了抗老化工艺对PP/ES土工布力学性能和抗紫外老化性能的影响。结果表明:添加抗老化母粒和TiO_(2)浸轧后整理的PP/ES土工布力学性能少许上升;该土工布紫外老化后的羰基吸收峰强度最弱,T 5%仅下降4.73℃,纵向和横向的断裂强度保留率仅下降26.55%和26.76%,表现出最佳的抗紫外老化性能。
基金financially supported by the Heilongjiang Provincial Natural Science Foundation of China (No. 201107)
文摘The microstructural evolution and mechanical properties of a spray-formed superalloy were studied in this paper. Based on a better understanding of the microstructural evolution of the spray-formed superalloy during solution treatment, an optimum solution treatment process was obtained, namely, at 1,140 °C for 6 h, and air cooling(AC). The effects of the ageing treatments on the mechanical properties of the post-solution-treated spray-formed superalloy were evaluated using ageing harden curves and tensile testing. The results indicated that the maximum hardness value was achieved at 850 °C for 8 h, AC. Due to co-precipitation of primary and secondary c0 precipitates during the heat treatment,the spray-formed superalloy obtained an excellent combination of yield strength(YS = 1,110 MPa), ultimate tensile strength(UTS = 1,503 MPa), ductility(elongation, EL = 21%) and excellent stress rupture properties at 650 °C(UTS = 1,209 MPa, EL = 15.8%). The heat treatment also improved the rupture life at 650 °C/950 MPa and 750 °C/539 MPa up to 140 h without rupturing. The tensile-fractured surfaces exhibit ductile transgranular failure feature. The optimum heat treatment process was determined to be 1,140 °C/6 h+850 °C/8 h+AC.
基金supported by the Fund of Independent Innovation in Shandong Province(2013CXB60201)the Fund of Transformation of Independent Innovation Achievements in Shandong(2014CGZH0102)the Fundamental Research Fund of Shandong University(2016JC016)
文摘Cu-Ag-RE alloys with different Ce contents were prepared by vacuum melting, and microstructure evolution and mechanical properties of Cu-Ag-Ce alloys were investigated by optical microscopy, scanning electronic microscopy with electron back-scattered diffraction and tensile test. The results indicated that a columnar to equiaxed transition in cast Cu-Ag-RE alloys was observed due to Ce addition and area of the region with equiaxed grains enlarged with increasing Ce content. Cold-rolled Cu-Ag-RE alloys in annealed condition exhibited a partially or fully recrystallized grain structure depending on the concentration of Ce. The average grain size decreased and texture components changed with increasing Ce content. The main brass-type texture component changed to be copper-type as the Ce content increased from 0.05 wt.% to 1.0 wt.%. The Cu-Ag-RE alloy with 0.2 wt.% Ce showed maximum ultimate tensile strength, while the sample with 1.0 wt.% Ce showed a better comprehensive mechanical property.