The formability of AA5052/polyethylene/AA5052 sandwich sheets was experimentally studied. Three kinds of AA5052/polyethylene/AA5052 sandwich specimens with different thicknesses of core materials were prepared by the ...The formability of AA5052/polyethylene/AA5052 sandwich sheets was experimentally studied. Three kinds of AA5052/polyethylene/AA5052 sandwich specimens with different thicknesses of core materials were prepared by the hot pressing adhesive method. Then, the uniaxial tensile tests were conducted to investigate the mechanical properties of AA5052/polyethylene/ AA5052 sandwich sheets, and the stretching tests were carried out to investigate the influences of polymer core thickness on the limit dome height of the sandwich sheet. The forming limit curves for three kinds of sandwich sheets were obtained. The experimental results show that the forming limit of the AA5052/polyethylene/AA5052 sandwich sheet is higher than that of the monolithic AA5052 sheet, and it increases with increasing the thickness of polyethylene core.展开更多
采用析氢法、失重法、极化曲线和电化学阻抗法测试了L-半胱氨酸对4 mol/L Na OH溶液中AA5052铝合金的缓蚀性能。结果表明:L-半胱氨酸的最佳缓蚀浓度为30 mmol/L;L-半胱氨酸在AA5052铝合金表面的吸附作用符合修正Langmuir曲线;L-半胱氨...采用析氢法、失重法、极化曲线和电化学阻抗法测试了L-半胱氨酸对4 mol/L Na OH溶液中AA5052铝合金的缓蚀性能。结果表明:L-半胱氨酸的最佳缓蚀浓度为30 mmol/L;L-半胱氨酸在AA5052铝合金表面的吸附作用符合修正Langmuir曲线;L-半胱氨酸缓蚀剂对AA5052铝合金的缓蚀机理为几何覆盖效应,抑制腐蚀反应的阴极过程,属于阴极型缓蚀剂。展开更多
Friction stir welding between AA5052-H32aluminium plates is performed by central composite design technique of response surface methodology.It is found that the welding parameters such as tool pin profile,tool rotatio...Friction stir welding between AA5052-H32aluminium plates is performed by central composite design technique of response surface methodology.It is found that the welding parameters such as tool pin profile,tool rotational speed,welding speed,and tool tilt angle play a major role in deciding the joint characteristics.The joints fabricated using tapered square pin profile tool with a tool rotational speed of600r/min,welding speed of65mm/min,and tool tilt angle of1.5°result in an unexpected weld efficiency of93.51%.Mathematical models are developed to map the correlation between the parameters and responses(ultimate tensile strength and elongation)and these models are optimized to maximize the ultimate tensile strength of the friction stir welded joint.Response plots generated from the mathematical models are used to interpret the interaction effects of the welding parameters on the response variables.Adequacy of the developed models is validated using analysis of variance(ANOVA)technique.Results from the confirmatory experiments plotted in scatter diagram show a good agreement with predicted models.Different grain structures in various zones of the weld are examined by observing the micro and macro structures of the weld.展开更多
基金Project(HIT.NSRIF.2009033) supported by the Scientific Research Foundation of Harbin Institute of Technology,China
文摘The formability of AA5052/polyethylene/AA5052 sandwich sheets was experimentally studied. Three kinds of AA5052/polyethylene/AA5052 sandwich specimens with different thicknesses of core materials were prepared by the hot pressing adhesive method. Then, the uniaxial tensile tests were conducted to investigate the mechanical properties of AA5052/polyethylene/ AA5052 sandwich sheets, and the stretching tests were carried out to investigate the influences of polymer core thickness on the limit dome height of the sandwich sheet. The forming limit curves for three kinds of sandwich sheets were obtained. The experimental results show that the forming limit of the AA5052/polyethylene/AA5052 sandwich sheet is higher than that of the monolithic AA5052 sheet, and it increases with increasing the thickness of polyethylene core.
文摘采用析氢法、失重法、极化曲线和电化学阻抗法测试了L-半胱氨酸对4 mol/L Na OH溶液中AA5052铝合金的缓蚀性能。结果表明:L-半胱氨酸的最佳缓蚀浓度为30 mmol/L;L-半胱氨酸在AA5052铝合金表面的吸附作用符合修正Langmuir曲线;L-半胱氨酸缓蚀剂对AA5052铝合金的缓蚀机理为几何覆盖效应,抑制腐蚀反应的阴极过程,属于阴极型缓蚀剂。
文摘Friction stir welding between AA5052-H32aluminium plates is performed by central composite design technique of response surface methodology.It is found that the welding parameters such as tool pin profile,tool rotational speed,welding speed,and tool tilt angle play a major role in deciding the joint characteristics.The joints fabricated using tapered square pin profile tool with a tool rotational speed of600r/min,welding speed of65mm/min,and tool tilt angle of1.5°result in an unexpected weld efficiency of93.51%.Mathematical models are developed to map the correlation between the parameters and responses(ultimate tensile strength and elongation)and these models are optimized to maximize the ultimate tensile strength of the friction stir welded joint.Response plots generated from the mathematical models are used to interpret the interaction effects of the welding parameters on the response variables.Adequacy of the developed models is validated using analysis of variance(ANOVA)technique.Results from the confirmatory experiments plotted in scatter diagram show a good agreement with predicted models.Different grain structures in various zones of the weld are examined by observing the micro and macro structures of the weld.
