作者：朱文波1, 谈建平1, 孙伯仲1, 常帅1, 裴玉冰2,3, 涂善东1
作者单位：1. 华东理工大学承压系统与安全教育部重点实验室, 上海 200237;
2. 长寿命高温材料国家重点实验室, 四川 德阳 618000;
3. 东方电气集团东方汽轮机有限公司, 四川 德阳 618000
关键词：纳米压痕;影响因素;有限元;测量误差;in718合金
摘要：
采用试验测试与有限元模拟相结合的方法，研究纳米压痕测量因素对in718合金力学行为的影响。结果表明，对于in718材料，存在明显的压痕尺寸效应，随着压入深度的增加，硬度逐渐降低，且在压入深度达到1000 nm之后硬度值的变化趋于稳定；当试样厚度与压入深度之比（“厚深比”）≥20之后，载荷位移曲线趋于一致，推荐最佳“厚深比”为20；摩擦系数对压痕的载荷-位移曲线几乎没有影响，但会影响压痕表面堆积轮廓，随着摩擦系数的增加，压痕表面材料的堆积逐渐减小，当摩擦系数达到0.2之后，表面材料堆积的减少逐渐趋于稳定；被压试样表面倾斜角对压痕的载荷-位移曲线有一定影响，倾斜角在5°以内时，压痕的载荷-位移曲线差别不大，峰值载荷最大误差均在5%以内，即可认为倾斜角≤5°时误差在可接受范围内。
the influence factors on mechanical behaviour test results of in718 by using nano-indentation method
zhu wenbo1, tan jianping1, sun bozhong1, chang shuai1, pei yubing2,3, tu shandong1
1. moe key laboratory of pressure systems and safety, east university of science and technology, shanghai 200237, china;
2. state key laboratory of long-life high temperature materials, deyang 618000, china;
3. dongfang electric corporation dongfang turbine co., ltd., deyang 618000, china
abstract: the effect of nano-indentation measurement factors on mechanical behavior of in718 alloy was studied by combining experimental test and finite element simulation. the results show that the hardness decreases gradually with the increase of indentation depth, and the change of hardness tends to be stable after the indentation depth reaches 1000 nm. when the ratio of thickness to indentation depth (thickness-depth ratio) is greater than or equal to 20, the load displacement curve tends to be consistent, and the best thickness-depth ratio is recommended to be 20. the friction coefficient has little effect on the load-displacement curve of the indentation, but it does affect the indentation surface profile. with the increase of the friction coefficient, the accumulation of materials on the indentation surface decreases gradually. when the friction coefficient reaches 0.2, the reduction of surface material accumulation tends to be stable. the surface inclination angle of the indented sample has a certain influence on the load-displacement curve of the indentation. when the inclination angle is within 5°, the load-displacement curve has little difference, and the maximum error of the peak load is within 5%. it can be considered that the error is within the acceptable range when the inclination angle is less than or equal to 5°.
keywords: nano-indentation;influence factors;finite element;measurement error;in718 alloy
2023, 49(6):30-35 收稿日期: 2021-11-30;收到修改稿日期: 2022-02-06
基金项目: 国家自然科学基金（52130511，52075174）
作者简介: 朱文波(1993-),男,安徽宣城市人,博士研究生,研究方向为纳米压痕力学性能测试
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