原位Al_(3)Ti颗粒增强Al-7Si合金纳米压入应变率敏感性  

Investigation on strain rate sensitivity of in-situ Al_(3)Ti particulatereinforced Al-7Si alloy by nanoindentation

作　　者：邢学刚 常超 杨雪霞[1] 郝鑫 王永胜[2] XING Xuegang;CHANG Chao;YANG Xuexia;HAO Xin;WANG Yongsheng(School of Applied Science,Taiyuan University of Science and Technology,Taiyuan 030024,China;College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原科技大学应用科学学院,太原030024 [2]太原理工大学材料科学与工程学院,太原030024

出　　处：《功能材料》2023年第12期12225-12230,共6页Journal of Functional Materials

基　　金：山西省基础研究计划(20210302124389,202103021224267,20210302123220);山西省高等学校科技创新项目(2021L043,2022L315);太原科技大学校级博士科研启动金(20222129);来晋工作优秀博士奖励资金(20222130)。

摘　　要：采用纳米压入方法研究了原位Al_(3)Ti颗粒增强Al-7Si合金室温压入应变率敏感性。控制压入应变率加载达到最大预设压入深度,基于连续刚度测量原理,研究不同加载应变率下压入硬度。结果表明,Sr元素添加将原位Al_(3)Ti颗粒增强铝合金中共晶Si相修饰为短纤维状。不同于铝合金基材,颗粒增强铝合金压入硬度表现出应变率敏感性。T6热处理后,共晶Si相球化为颗粒状,材料微观组织均匀性增强,压入应变率敏感性不明显。深冷处理后α-Al晶粒细化,共晶Si相尺寸进一步减小,材料应变率敏感性提高。Nanoindentation tests were conducted on in-situ Al_(3)Ti particulate reinforced Al-7Si alloy to investigate the strain rate sensitivity at room temperature.The indenter was loaded to a fixed maximum load with different loading strain rates.Hardness was investigated based on continuous stiffness measurement.Results show that the eutectic Si in Al_(3)Ti particulate reinforced Al-7Si is modified to short fibrous morphology due to addition of Sr.Al_(3)Ti particulate reinforced Al-7Si exhibits dependence on loading strain rate in terms of hardness.T6 heat treatment spheroidizes eutectic Si phases into round Si particles.Microstructure uniformity of materials is enhanced and the strain rate sensitivity becomes less pronounced.Strain rate sensitivity of the specimen is improved after cryogenic treatment,along with the refinement ofα-Al grains and eutectic Si.

关 键 词：颗粒增强铝合金 纳米压入 硬度 应变率敏感性 

分 类 号：O344.3[理学—固体力学]