Small Size Specimens Methods for Evaluation of Mechanical Properties

Abstract

The evaluation of actual mechanical properties of the in-service structures after some time of operation or determination of local properties for detailed FEM simulation yields the necessity to obtain relevant material data with high accuracy from small volume of the experimental material. Therefore, non-destructive or semi-destructive techniques using small size samples are being developed. The use of small-scale samples also enables the evaluation of material properties in various locations of tested component; for example, the mechanical properties of the individual regions of welds, local properties determination for properties anisotropy assessment and properties determination in cases when small volume of the experimental material is available e.g. residual service life assessment of in service components, bulk nanostructured materials… There are shown results of small size tensile tests (M-TT) and small sized fatigue tests (SFT). In the case of small size specimens testing a machining becomes more pronounced that in the case of standard sized specimens. The current study brings information on the machining influence on the expected results obtained by small size specimens in the case of quasi-static tensile tests and fatigue test.

Small‐sized specimen design with the provision for high‐frequency bending‐fatigue testing

“…Utilizing subsized specimens for the fatiguerelated studies has been repeatedly reported in the literature. [35][36][37] Small-sized specimens are commonly introduced and used when limited amount of testing material is available, for the determination of fatigue properties for nanostructured materials, assessment of dilatometric samples used for thermal and thermomechanical treatment development, local properties of weld joints, and so on. 38 In addition, a wide variety of metallic mechanical parts and components are in the form of sheets-such as metal bellows and belts-where the thin sheet fatigue properties need to be studied.…”

“…39 Utilizing subsized samples also enables the study of residual service life assessment of in-service components and local properties determination for anisotropic properties assessment. 37 The primary motivation behind this study is its potential advantage for AM material testing. The scientific barrier to accomplish the rapid qualification of metallic AM parts is the lack of high-fidelity processing strategy-structure-performance (PSP) relationships.…”