Flat-Top Cylinder Indenter for Mechanical Characterization: A Report of Industrial Applications

Abstract

FIMEC (flat-top cylinder indenter for mechanical characterisation) is an instrumented indentation test employing a cylindrical punch. It has been used to determine the mechanical properties of metallic materials in several applications of industrial interest. This work briefly describes the technique and the theory of indentation with a flat-ended punch. The flat indentation of metals has been investigated through experimental tests, and an equation has been derived to calculate the yield stress from the experimental data in deep indentation. The approach is supported by many data on various metals and alloys. Some selected case studies are presented in the paper: (i) crank manufacturing through pin squeeze casting; (ii) the evaluation of the local mechanical properties in a carter of complex geometry; (iii) the qualification of Al billets for extrusion; (iv) stress–relaxation tests on CuCrZr heat sinks; (v) the characterization of thick W coatings on CuCrZr alloy; (vi) the measure of the local mechanical properties of the molten-zone (MZ) and the heat-affected zone (HAZ) in welded joints. The case studies demonstrate the great versatility of the FIMEC test which provides information not available by employing conventional experimental techniques such as tensile, bending, and hardness tests. On the basis of theoretical knowledge and large amount of experimental data, FIMEC has become a mature technique for application on a large scale in industrial practice.

A Novel Superhard, Wear-Resistant, and Highly Conductive Cu-MoSi2 Coating Fabricated by High-Speed Laser Cladding Technique

“…Figure 11 d shows the resistivity of the Cu- x MoSi 2 ( x = 10, 15, 20, 25, 30, wt.%) coating as 0.084 × 10 −6 Ω·m, 0.120 × 10 −6 Ω·m, 0.128×10 −6 Ω·m, 0.144 × 10 −6 Ω·m, and 0.173 × 10 −6 Ω·m. Compared to other copper alloy coating systems [ 4 , 5 , 6 , 7 , 8 , 9 , 10 ] (with a hardness of 684 HV and a resistivity of 3.51 × 10 −6 Ω·m), the coating still maintains a relatively high electrical conductivity. From the conductive mechanism of metals [ 33 ], when an electron wave passes through an ideal crystal lattice at absolute zero, it will propagate unhindered by scattering, and the material is an ideal conductor.…”

“…Manufacturing copper components with exceptional super hardness, impressive wear resistance, and elevated conductivity is now a necessity. Metal matrix composites (MMCs) comprise the properties of metal matrices (ductility and toughness) and reinforcement phases (high strength and stiffness) [4][5][6][7][8], which enables the superior mechanical and functional properties such as excellent wear resistance, controllable coefficient of thermal expansion, and good thermal shock resistance. However, MMCs normally gives rise to notable dislocation pile-ups and severe stress concentration at grain boundaries [9,10]; extensive research has been relying on manipulating the uniform distribution of the reinforcement phase as an innovative approach for designing the microstructural architecture of MMCs to surmount such a dilemma.…”

The Instrumented Indentation Test: An Aiding Tool for Material Science and Industry

“…A number of scientists, users, developers, engineers, and technical experts from the academic, industrial, and research areas have contributed to this first volume of the Special Issue on The Instrumented Indentation Test: An Aiding Tool for Materials Science and Industry. The present state of the art on the subject indicates that, in spite of promising experiences which encourage the transfer of IIT from the laboratory to industry [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 ], other factors currently act as an obstacle to its use (see, for instance [ 14 , 16 ]).…”

“…The comprehensive review by Montanari and Varone [ 10 ] offers net evidence on the simplicity, indentation size effect-free, roughness-insensitivity, and versatility features of flat-punch macro-indentation (FIMEC). These features are all very desirable for industrial applications.…”

Accurate Estimation of Yield Strength and Ultimate Tensile Strength through Instrumented Indentation Testing and Chemical Composition Testing

“…A combination of indentations, with a flat indenter and numerical analysis, was used in [6] in extracting the full hardening curve from grade X80 pipe, with validation against tensile data. The same authors used the technique to assess the mechanical properties of welds in X80 pipe in [7], and an overall review of the flat indenter technique was presented in [8]. IIT has also been used to measure residual stresses in steels [9].…”