温度对铸造Al-Si9-Cu3-Fe1合金缸体力学性能与高周疲劳性能的影响  

Effect of Temperature on Mechanical Properties and High-cycle Fatigue Property of Cast Al-Si9-Cu3-Fe1 Alloy Cylinder Block

作　　者：王立新[1] 宋鸿武[2] WANG Lixin;SONG Hongwu(Propulsion Systems, Pan Asia Technical Automotive Center Co., Ltd., Shanghai 201201, China;Institute of Metal Research, Chinese Academy of Sciences, Shenyang Liaoning 110016, China)

机构地区：[1]泛亚汽车技术中心有限公司驱动系统部,上海201201 [2]中国科学院金属研究所,辽宁沈阳110016

出　　处：《上海金属》2020年第4期56-60,65,共6页Shanghai Metals

摘　　要：从实际铸造Al-Si9-Cu3-Fe1合金缸体上取样,分别在不同温度(室温、150、200、250℃)下进行拉伸和高周疲劳试验(104~107周次),获得了合金在不同温度下的力学性能、应力-寿命(S-N)曲线及疲劳极限,然后采用扫描电镜分析疲劳断口形貌。结果表明:随着温度的升高,合金的抗拉强度降低,断后伸长率增加;温度对合金高周疲劳性能的影响并不明显,这是因为疲劳极限在很大程度上决定于缺陷而非基体材料的性能。因此实际铸造缸体在不同温度下的力学性能差别较大,而高周疲劳性能差别较小。Samples were taken from cast Al-Si9-Cu3-Fe1 alloy cylinder blocks and subjected to tensile test and high-cycle fatigue test(Nf=104 to 107 cycles)at different temperatures(room temperature,150℃,200℃and 250℃).Mechanical properties,stress-life(S-N)curves and fatigue limit of the alloy at different temperatures were obtained,and fatigue fracture morphology was analyzed by SEM.The results showed that with the increase of temperature,the tensile strength of the alloy decreased and elongation increased;the temperature had a little effect on the high cycle fatigue property of the alloy because the fatigue limit depends mostly on the defects rather than the property of matrix material.Therefore,the commercial cylinder blocks at different temperatures differed greatly in mechanical properties,but less in high cycle fatigue property.

关 键 词：温度 力学性能 高周疲劳 铸造铝合金 S-N曲线 

分 类 号：TG1[金属学及工艺—金属学]