Na变质对ZL101合金低温力学性能的影响
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摘要
研究了Na变质处理对ZL101合金显微组织中Si相形貌和低温力学性能的影响。结果表明,Na变质处理可以改善合金中Si相形貌,大多数Si相由粗大的长条状和板片状变成了细小的纤维状,降低了Si相对铝基体的割裂作用。Na变质后,Si相尺寸减小,在低温下断裂时所需的临界切应力增大,产生的微裂纹较小,合金在低温下的强度和伸长率提高,其抗拉强度、屈服强度和伸长率分别为186MPa、161MPa和6.60%。
The effects of Na modification on the morphology of Si phase and tensile properties of ZL101 alloy at low temperature were investigated.The results show that the Na modification can improve the morphology of the Si phase in the alloy.The Si phase is changed from a coarse lamellar structure to a fine fiber one,which reduces the Si splitting effect on the aluminum matrix.After Na modification,the size of Si phase is decreased.The critical shearing stress required for fracture is increased at low temperature,resulting in smaller microcracks.The mechanical properties,such as tensile strength,yield strength and elongation,of the alloy are improved at low temperature,which reach 186 MPa,161 MPa and 6.60%,respectively.
The effects of Na modification on the morphology of Si phase and tensile properties of ZL101 alloy at low temperature were investigated.The results show that the Na modification can improve the morphology of the Si phase in the alloy.The Si phase is changed from a coarse lamellar structure to a fine fiber one,which reduces the Si splitting effect on the aluminum matrix.After Na modification,the size of Si phase is decreased.The critical shearing stress required for fracture is increased at low temperature,resulting in smaller microcracks.The mechanical properties,such as tensile strength,yield strength and elongation,of the alloy are improved at low temperature,which reach 186 MPa,161 MPa and 6.60%,respectively.
引文
[1]刘洲,何玉怀,刘昌奎,等.ZL101合金的拉伸断裂特征[J].机械工程材料,2014,38(2):82-86.
[2] EIKEN J,APEL M,LIANG S M,et al.Impact of P and Sr on solidification sequence and morphology of hypoeutectic Al-Si alloys:Combined thermodynamic computation and phase-field simulation[J].Acta Materialia,2015,98:152-163.
[3] SUN J F,ZHANG L,WU G H,et al.Refinement of primary Si in Al-20%Si alloy by MRB through phosphorus additions[J].Journal of Materials Processing Technology,2015,225:485-491.
[4]李豹.AlSi7Mg合金共晶硅变质规律及其微观机制[D].哈尔滨:哈尔滨工业大学,2011.
[5] HAFIZ M F,KOBAYASHI T.Fracture toughness of eutectic AlSi casting alloy with different microstructural features[J].Journal of Materials Science,1996,31:6 195-6 200.
[6] SRIVASTAVA V C,OJHA S N.Microstructure and wear characteristics of spray formed and hot extruded Al-Si alloys[J].Materials Science and Technology,2004,20(12):1 632-1 638.
[7]苏辉,吕柏林.Al-Si过共晶合金拉伸断裂过程的研究[J].材料开发与应用,2008,23(2):22-23.
[8]马广辉,李润霞,白彦华,等.Si相对铸造Al-Si合金低温拉伸断裂行为的影响[J].中国有色金属学报,2016,26(8):1 615-1 623.
[9] OSAMU U.Mechanical properties of thermos-mechanical treated hyper-eutectic Al-Si-(Fe,Mn,Cu)materials[J].Materials Transactions,2005,46(12):2 616-2 623.
[10] RINCON E,LOPEZ H F,CISNEROS M M,et al.Temperature effects on the tensile properties of cast and heat treated aluminum alloy A319[J].Materials Science and Engineering,2009,A39(7):633-639.
[11]徐建辉,龙文元,方立高.钠盐变质铝硅合金中的共晶硅相[J].航空材料学报,2000,20(1):18-21.
[12]马广辉.铸造Al-Si-Mg合金低温力学性能及其断裂行为[D].沈阳:沈阳工业大学,2016.
[13] YEH J W,LIU W P.The cracking mechanism of silicon particles in an A357 aluminum alloy[J].Metallurgical and Materials Transactions,1996,A27(11):3 558-3 568.
[2] EIKEN J,APEL M,LIANG S M,et al.Impact of P and Sr on solidification sequence and morphology of hypoeutectic Al-Si alloys:Combined thermodynamic computation and phase-field simulation[J].Acta Materialia,2015,98:152-163.
[3] SUN J F,ZHANG L,WU G H,et al.Refinement of primary Si in Al-20%Si alloy by MRB through phosphorus additions[J].Journal of Materials Processing Technology,2015,225:485-491.
[4]李豹.AlSi7Mg合金共晶硅变质规律及其微观机制[D].哈尔滨:哈尔滨工业大学,2011.
[5] HAFIZ M F,KOBAYASHI T.Fracture toughness of eutectic AlSi casting alloy with different microstructural features[J].Journal of Materials Science,1996,31:6 195-6 200.
[6] SRIVASTAVA V C,OJHA S N.Microstructure and wear characteristics of spray formed and hot extruded Al-Si alloys[J].Materials Science and Technology,2004,20(12):1 632-1 638.
[7]苏辉,吕柏林.Al-Si过共晶合金拉伸断裂过程的研究[J].材料开发与应用,2008,23(2):22-23.
[8]马广辉,李润霞,白彦华,等.Si相对铸造Al-Si合金低温拉伸断裂行为的影响[J].中国有色金属学报,2016,26(8):1 615-1 623.
[9] OSAMU U.Mechanical properties of thermos-mechanical treated hyper-eutectic Al-Si-(Fe,Mn,Cu)materials[J].Materials Transactions,2005,46(12):2 616-2 623.
[10] RINCON E,LOPEZ H F,CISNEROS M M,et al.Temperature effects on the tensile properties of cast and heat treated aluminum alloy A319[J].Materials Science and Engineering,2009,A39(7):633-639.
[11]徐建辉,龙文元,方立高.钠盐变质铝硅合金中的共晶硅相[J].航空材料学报,2000,20(1):18-21.
[12]马广辉.铸造Al-Si-Mg合金低温力学性能及其断裂行为[D].沈阳:沈阳工业大学,2016.
[13] YEH J W,LIU W P.The cracking mechanism of silicon particles in an A357 aluminum alloy[J].Metallurgical and Materials Transactions,1996,A27(11):3 558-3 568.