检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
作 者:蔡绍祥 李延军 黄燕萍 郭玉良 CAI Shaoxiang;LI Yanjun;HUANG Yanping;GUO Yuliang(College of Textile,Garment and Design,Changshu Institute of Technology,Changshu 215500,Jiangsu,China;College of Materials Science and Engineering,Nanjing Forestry University,Nanjing 210037,China;Architectural Engineering Institute,Nantong Institute of Technology,Nantong 226007,Jiangsu,China)
机构地区:[1]常熟理工学院纺织服装与设计学院,江苏常熟215500 [2]南京林业大学材料科学与工程学院,南京210037 [3]南通理工学院建筑工程学院,江苏南通226007
出 处:《林业工程学报》2021年第4期64-71,共8页Journal of Forestry Engineering
基 金:国家自然科学基金(31570552)。
摘 要:通过改变纳米压痕过程中加载函数的具体参数值,研究了加载载荷与木材细胞壁弹性模量、硬度和蠕变性能的关系,并探求在木材细胞壁线性黏弹性范围内合适的加载载荷。研究结果表明:在测试过程中,当加载载荷逐渐增大时,马尾松木材细胞壁弹性模量变化明显;载荷为200μN时,弹性模量达到最大值,随后保持相对稳定;载荷达到400μN时弹性模量开始减小;改变加载载荷测得的木材细胞壁硬度随加载载荷的增加而逐渐变大,最大增幅为10%左右;探针压痕深度随着加载载荷的增加逐渐变大,载荷增加对压痕深度影响显著;蠕变率随着加载载荷的增加而逐渐增加,最大增幅为70%;应变率和蠕变应力都具有二段式变化趋势,第1阶段在4~6 s时变化较大,第2阶段在7~10 s时变化平缓。利用幂次律对试验数据进行分析表明,加载力为150~300μN时可近似认为是线性黏弹性行为。然后结合不同加载载荷对弹性模量和硬度的影响,综合相关参数可以判断,在对马尾松之类的针叶材进行纳米压痕试验时,合适的加载载荷范围为200~300μN。During the nano-indentation tests, the density, hardness and indentation depth of the material have great influence on the test results. The added load of different materials during the test is also different. Therefore, it is very important for the accuracy of the test results to explore the appropriate added load of wood cell wall in the nano-indentation test. In this study, the relationship between the added load and the modulus of elastic, hardness, and creep property of the wood cell wall was studied by changing the specific parameters of the loading function during the process of nano-indentation. The suitable load values in the linear viscoelastic range were obtained. The results showed that: the modulus of elastic of masson’s pine cell wall changed obviously when the loading load increased gradually;when the load was 200 μN, the modulus of elasticity reached the maximum value and then remained stable;when the load reached 400 μN, the modulus of elasticity decreased;meanwhile, the hardness of wood cell wall increased with the increase of load. The creep rate increased with the increase of the added load, both the strain rate and creep stress had a two-stage change trend, the first stage had a large change at 4-6 s, while the second stage had a gentle change at 7-10 s. The power law was used to analyze the experimental data and it was shown that when the loading force was 150-300 μN, it could be approximately considered as a type of linear viscoelastic behavior. Based on the relevant parameters, it could be determined that the suitable loading range was 200-300 μN for the nano-indentation experiment on needles such as masson’s pine. By applying the correlation between the mechanical measurement of wood cell wall and added load developed in this study, the nano-indentation method can provide more precise, reliable and repeatable measurements of hardness, Young’s modulus and other mechanical properties for most wood species to help exploring new research, reduce product failures and accelerate the t
分 类 号:S781.2[农业科学—木材科学与技术]
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:216.73.216.249