时效对7901环氧树脂力学性能的影响
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摘要
用浇铸固化成型的方法制备7901环氧树脂的拉伸、压缩和扭转试样,将其放置在室温环境下不同时长进行时效处理,采用差示扫描量热法对树脂进行固化度测试,结果表明:在此工艺下,树脂的固化达到完全且固化度不随时间变化。对置放不同时长的树脂进行力学性能测试,测试研究发现:树脂的拉伸,压缩和剪切弹性性能不随时间产生变化,但拉伸断裂强度、压缩屈服强度和剪切屈服强度随时间增长而降低,其中置放八个月和十三个月的树脂的拉伸强度较一个月的树脂分别减小7%和13%,而压缩和剪切屈服强度在八个月后达到稳定,较置放一个月的树脂分别减小10%和20%。树脂的力学性能具有时效性,在复合材料微观力学性能预测中,应该输入对应时段的树脂基体性能数据。
A casting method was used to prepare the tensile,compressive and torsional specimens of 7901 epoxy resin. The specimens were stored under room temperature for aging treatment. Cured degree of the resin was tested using differential scanning calorimetry(DSC) and the results show that under this method,the resin are fully cured and the degree of curing did not change with time. Mechanical tests were performed on the specimens,and characteristic points of stress-strain relations were measured. The results show that the elastic properties of tension,compression and torsion remain unchanged with time. However,the ultimate tensile strength of 8-month and 13-month resin are decreased by 7% and 13% compared to the 1-month resin,whereas the compressive and shear yield strength keep invariant after eight months with 10% and 20% lowing,respectively. The strengths of resin change with time,and the corresponding data should be inputted while predicting the behavior of composite materials.
A casting method was used to prepare the tensile,compressive and torsional specimens of 7901 epoxy resin. The specimens were stored under room temperature for aging treatment. Cured degree of the resin was tested using differential scanning calorimetry(DSC) and the results show that under this method,the resin are fully cured and the degree of curing did not change with time. Mechanical tests were performed on the specimens,and characteristic points of stress-strain relations were measured. The results show that the elastic properties of tension,compression and torsion remain unchanged with time. However,the ultimate tensile strength of 8-month and 13-month resin are decreased by 7% and 13% compared to the 1-month resin,whereas the compressive and shear yield strength keep invariant after eight months with 10% and 20% lowing,respectively. The strengths of resin change with time,and the corresponding data should be inputted while predicting the behavior of composite materials.
引文
[1]Huang Zhenming,Zhou Yexin.Strength of fibrous composites[M].Zhejiang:Zhejiang University Press,2011.
[2]Kinloch A,Young R.Fracture behaviour of polymers[M].London:Applied Science Publishers Ltd.1983.286-289.
[3]Littell J D,Ruggeri C R,Goldberg R K,et al.Measurement of epoxy resin tension,compression,and shear stress-strain curves over a wide range of strain rates using small test specimens[J].Journal of Aerospace Engineering,2008,21(3):162-173.
[4]Fiedler B,Hojo M,Ochiai S,et al.Failure behavior of an epoxy matrix under different kinds of static loading[J].Compos.sci.technol,2001,61(11):1 615-1 624.
[5]Jordan J L,Foley J R,Siviour C R.Mechanical properties of Epon826/DEA epoxy[J].Mechanics of Time-Dependent Materials,2008,12(3):249-272.
[6]Behzadi S,Jones F R.Yielding behavior of model epoxy matrices for fiber reinforced composites:effect of strain rate and temperature[J].Journal of Macromolecular Science Part B,2005,44(6):993-1 005.
[7]Khan M Z S,Simpson G,Townsend C R.A comparison of the mechanical properties in compression of two resin systems[J].Materials Letters,2002,52(3):173-179.
[8]Chen Weinong,Lu Frank,Cheng Ming.Tension and compression tests of two polymers under quasi-static and dynamic loading[J].Polymer Testing,2002,21(2):113-121.
[9]王绪财,彭刚,冯家臣,等.应变率对乙烯基酯树脂压缩力学行为影响的研究[J].工程塑料应用,2010,38(5):59-61.Wang Xucai,Peng Gang,Feng Jiachen,et al.Effect of strain rate on compressive behavior of vinyl ester resin[J].Engineering Plastics Application,2010,38(5):59-61.
[10]Fard M Y,Liu Yingtao,Chattopadhyay A,et al.Characterization of epoxy resin including strain rate effects using digital image correlation system[J].Journal of Aerospace Engineering,2012,25(2):308-319.
[11]安静波,王仲莉.不饱和聚酯浇铸体拉伸性能与固化度的关系[J].热固性树脂,1998(2):26-28.An Jingbo,Wang Zhongli.The relation of the tensile property of unsaturated polyester casting matrix to its curing degree[J].Thermosetting Resin,1992(2):26-28.
[12]刘卓峰,冯学斌,肖加余,等.低粘度环氧树脂浇铸体性能与固化度的关系[J].材料导报,2009,23(20):26-28.Liu Zhuofeng,Feng Xuebin,Xiao Jiayu,et al.Relation of the property of a low viscosity epoxy resin casting matrix to its degree of cure[J].Materials Review,2009,23(20):26-28.
[13]Rudolf R.Thermosets[M].Shanghai:Donghua University Press,2009,91-94.
[14]Kalidindi S R,Abusafieh A,El-Danaf E.Accurate characterization of machine compliance for simple compression testing[J].Experimental Mechanics,1997,37(2):210-215.
[2]Kinloch A,Young R.Fracture behaviour of polymers[M].London:Applied Science Publishers Ltd.1983.286-289.
[3]Littell J D,Ruggeri C R,Goldberg R K,et al.Measurement of epoxy resin tension,compression,and shear stress-strain curves over a wide range of strain rates using small test specimens[J].Journal of Aerospace Engineering,2008,21(3):162-173.
[4]Fiedler B,Hojo M,Ochiai S,et al.Failure behavior of an epoxy matrix under different kinds of static loading[J].Compos.sci.technol,2001,61(11):1 615-1 624.
[5]Jordan J L,Foley J R,Siviour C R.Mechanical properties of Epon826/DEA epoxy[J].Mechanics of Time-Dependent Materials,2008,12(3):249-272.
[6]Behzadi S,Jones F R.Yielding behavior of model epoxy matrices for fiber reinforced composites:effect of strain rate and temperature[J].Journal of Macromolecular Science Part B,2005,44(6):993-1 005.
[7]Khan M Z S,Simpson G,Townsend C R.A comparison of the mechanical properties in compression of two resin systems[J].Materials Letters,2002,52(3):173-179.
[8]Chen Weinong,Lu Frank,Cheng Ming.Tension and compression tests of two polymers under quasi-static and dynamic loading[J].Polymer Testing,2002,21(2):113-121.
[9]王绪财,彭刚,冯家臣,等.应变率对乙烯基酯树脂压缩力学行为影响的研究[J].工程塑料应用,2010,38(5):59-61.Wang Xucai,Peng Gang,Feng Jiachen,et al.Effect of strain rate on compressive behavior of vinyl ester resin[J].Engineering Plastics Application,2010,38(5):59-61.
[10]Fard M Y,Liu Yingtao,Chattopadhyay A,et al.Characterization of epoxy resin including strain rate effects using digital image correlation system[J].Journal of Aerospace Engineering,2012,25(2):308-319.
[11]安静波,王仲莉.不饱和聚酯浇铸体拉伸性能与固化度的关系[J].热固性树脂,1998(2):26-28.An Jingbo,Wang Zhongli.The relation of the tensile property of unsaturated polyester casting matrix to its curing degree[J].Thermosetting Resin,1992(2):26-28.
[12]刘卓峰,冯学斌,肖加余,等.低粘度环氧树脂浇铸体性能与固化度的关系[J].材料导报,2009,23(20):26-28.Liu Zhuofeng,Feng Xuebin,Xiao Jiayu,et al.Relation of the property of a low viscosity epoxy resin casting matrix to its degree of cure[J].Materials Review,2009,23(20):26-28.
[13]Rudolf R.Thermosets[M].Shanghai:Donghua University Press,2009,91-94.
[14]Kalidindi S R,Abusafieh A,El-Danaf E.Accurate characterization of machine compliance for simple compression testing[J].Experimental Mechanics,1997,37(2):210-215.