−A newly developed hardness test based on equivalent indentation depth is currently expected to be the only hardness test method that enables seamless evaluations of hardness across different hardness scales in all load ranges from nanoscopic to macroscopic in an industrial friendly manner because the new method is free from the shortcomings of the instrumented indentation method, which require...

Instrumented indentation test has been extensively applied to study the mechanical properties such as elastic modulus of different materials. The Oliver–Pharr method to measure the elastic modulus from an indentation test was originally developed for single phase materials. During a spherical indentation test on shape memory alloys (SMAs), both austenite and martensite phases exist and evolve i...

In the present article, a new method for the determination of the hardening law using the load displacement curve, F–h, of a spherical indentation test is developed. This method is based on the study of the error between an experimental indentation curve and a number of finite elements simulation curves. For the smaller values of these errors, the error distribution shape is a valley, which is ...

Relaxation indentation experiments using atomic force microscopy (AFM) are used to obtain viscoelastic material properties of soft samples. The quasilinear viscoelastic (QLV) model formulated by Fung (1972, "Stress Strain History Relations of Soft Tissues in Simple Elongation," in Biomechanics, Its Foundation and Objectives, Prentice-Hall, Englewood Cliffs, NJ, pp. 181-207) for uniaxial compres...

The high-temperature hardness test has a wide range of applications, but lacks test standards. The purpose of this study is to develop a finite element method (FEM) model of the relationship between the high-temperature hardness and high-temperature, quasi-static compression experiment, which is a mature test technology with test standards. A high-temperature, quasi-static compression test and ...

Indentation techniques for assessing fracture toughness are attractive due to the simplicity and expediency of experiments, and because they potentially allow the characterization of both local and bulk fracture properties. Unfortunately, rarely have such techniques been proven to give accurate fracture toughness values. This is a concern, as such techniques are seeing increasing usage in the s...

It is crucial to understand the creep behavior of Pb-free solder alloys in electronic packaging. Typical service environments are between 298 and 373K. The thermal mismatch induced stresses acting on solder joints result in extensive rate-dependent plastic deformation. The solder alloy is potentially the weakest component in the electronic package because normal operating temperatures are alrea...

Time dependent plastic deformation in metals can occur at high temperatures. Typically the creep test is conducted to characterize the deformation features; however, the conventional uniaxial power-law creep test may be impractical for small scale materials. Accordingly, instrumented indentation techniques are frequently employed. This study concerns the employment of instrumented indentation t...

 The Vickers hardness test can cover an extensive range of test loads from several gram-force (gf) to 100 kilogram-force (kgf) with a single hardness scale. It is one of the most reliable strength tests because the simplicity of the testing theory and the indenter shape minimizes variances among hardness values obtained. The most vulnerable aspect of the Vickers method is an error when measuri...