Scholarlink

Background <p>The portable automated ball indentation (PABI) is an effective non-destructive test method for evaluating mechanical properties of alloys. The technique suffers from sink-in / pile-up surrounding the indentation, which contributes 5–50% discrepancy in quantified data. Approximation of effective contact area either by LVDT or microscopy becomes inconvenient and erroneous.</p> Objective <p>The present investigation aims at exploring the influence of indenter diameter, pile-up/sink-in behavior, and contact mechanics during indentation on the mechanical properties of alloys. A modification in the existing portable automated ball indentation technique has been proposed with the aid of finite element modelling to eradicate the limitation in estimating actual contact diameter. Data obtained after modification have been compared with conventional tensile test results to establish the reliability of the technique.</p> Methods <p>Cr-steel and 304SS were chosen for the PABI experiment. From Load-depth <b>(</b><Emphasis Type="BoldItalic">P-</Emphasis><b>δ)</b> curves of PABI, true stress-true strain (σ<sub>t</sub>-ε<sub>p</sub>) plots were produced. The flow characteristic of alloys surrounding the indentation was analyzed using finite element modeling (FEM). The process was repeated with various diameter indenters to produce different extent of pile-up/sink-in. The characteristic was correlated with indenter size, contact load, contact friction, contact stress, and indentation depth using FEM.</p> Results <p>Pile-up/sink-in was primarily controlled by the indenter size apart from strain-hardening exponent, and contact stress of the alloy. Experimental procedure was modified by introducing FEM during PABI experiment. Subsequently, mechanical properties of alloys were evaluated and compared with conventional tensile test results.</p> Conclusions <p>The modified technique provided an effective solution against sink-in/pile-up effect, caused predominantly by the indenter diameter. The modified technique exhibited potential in producing reliable, and consistent data on mechanical properties of alloys without destructing them.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Experimental and Finite Element Analysis of Ball Indentation for Eradicating Indenter Size Effect during Evaluation of Mechanical Property of Alloys

  • 期刊论文

  • 发表日期：

    2026年6月23日

查看全文
  • M. Das,
  • A. K. Metya,
  • M. Ghosh

摘要

Background

The portable automated ball indentation (PABI) is an effective non-destructive test method for evaluating mechanical properties of alloys. The technique suffers from sink-in / pile-up surrounding the indentation, which contributes 5–50% discrepancy in quantified data. Approximation of effective contact area either by LVDT or microscopy becomes inconvenient and erroneous.

Objective

The present investigation aims at exploring the influence of indenter diameter, pile-up/sink-in behavior, and contact mechanics during indentation on the mechanical properties of alloys. A modification in the existing portable automated ball indentation technique has been proposed with the aid of finite element modelling to eradicate the limitation in estimating actual contact diameter. Data obtained after modification have been compared with conventional tensile test results to establish the reliability of the technique.

Methods

Cr-steel and 304SS were chosen for the PABI experiment. From Load-depth (P-δ) curves of PABI, true stress-true strain (σt-εp) plots were produced. The flow characteristic of alloys surrounding the indentation was analyzed using finite element modeling (FEM). The process was repeated with various diameter indenters to produce different extent of pile-up/sink-in. The characteristic was correlated with indenter size, contact load, contact friction, contact stress, and indentation depth using FEM.

Results

Pile-up/sink-in was primarily controlled by the indenter size apart from strain-hardening exponent, and contact stress of the alloy. Experimental procedure was modified by introducing FEM during PABI experiment. Subsequently, mechanical properties of alloys were evaluated and compared with conventional tensile test results.

Conclusions

The modified technique provided an effective solution against sink-in/pile-up effect, caused predominantly by the indenter diameter. The modified technique exhibited potential in producing reliable, and consistent data on mechanical properties of alloys without destructing them.