Publication detail

Measurement of mechanical and fatigue properties using unified, simple-geometry specimens: cold spray additively manufactured pure metals

ČÍŽEK, J. KOVAŘÍK, O. ČUPERA, J. KONDAS, J. BAJER, T. ŠIŠKA, F. MICHAELA, J. SEINER, H.

Original Title

Measurement of mechanical and fatigue properties using unified, simple-geometry specimens: cold spray additively manufactured pure metals

Type

journal article in Web of Science

Language

English

Original Abstract

A methodology that allows joint determination of fundamental engineering properties of materials/components vital to their efficient design and a safe service lifetime operation is presented. Using a combination of recently developed techniques, a simultaneous assessment of mechanical properties, fatigue crack growth rates, as well as fracture toughness is described. All these are performed using unified-geometry samples that are simple and easy to produce. The mechanical properties are measured in tensile and compressive modes, while the combination of developed bending test methods (quasi-static four-point bending and fatigue bending) enables to cover the fatigue loading from very low loads corresponding to crack propagation threshold values up to the high loads corresponding to a static fracture of the fracture toughness test. To validate and complement the bending data, additional resonant ultrasonic measurements of the corresponding properties are carried out. The methodology is partially suitable for testing of cold sprayed deposits. Therefore, Al, Cu, Ni and Ti deposits are tested and compared to cold-rolled sheet reference samples. The results are quantified in the form of NASGRO equation, widely used in software for prediction of fatigue lives. Together, the obtained set of data may be readily used for modeling of the performance of cold sprayed parts. Finally, fractographic analysis of the failed specimens is presented to describe the mechanisms leading to failure. At low loads, the reference sheets and the cold sprayed deposits exhibit similar behavior, where the cracks grow in a trans-crystalline mode without any significant interaction with deposit particle boundaries. Contrary to this, the behavior changes at higher loads: the particle interfaces in the cold sprayed deposits become the weak point and the cracks grow at high rates by inter-particle decohesion, while the sheet materials generally fail by striation mechanism at much lower rates.

Keywords

kinetic spraystress strainfracture toughnessfatigue crack growth ratefour-point bending

Authors

ČÍŽEK, J.; KOVAŘÍK, O.; ČUPERA, J.; KONDAS, J.; BAJER, T.; ŠIŠKA, F.; MICHAELA, J.; SEINER, H.

Released

5. 2. 2021

ISBN

0257-8972

Periodical

Surface and Coatings Technology

Year of study

412

Number

126929

State

Swiss Confederation

Pages from

1

Pages to

12

Pages count

12

URL

https://www.sciencedirect.com/science/article/pii/S025789722100102X

BibTex

@article{BUT170092,
  author="Jan {Čížek} and Ondřej {Kovařík} and Jan {Čupera} and Jan {Kondas} and Tomáš {Bajer} and Filip {Šiška} and Janovská {Michaela} and Hanuš {Seiner}",
  title="Measurement of mechanical and fatigue properties using unified, simple-geometry specimens: cold spray additively manufactured pure metals",
  journal="Surface and Coatings Technology",
  year="2021",
  volume="412",
  number="126929",
  pages="1--12",
  doi="10.1016/j.surfcoat.2021.126929",
  issn="0257-8972",
  url="https://www.sciencedirect.com/science/article/pii/S025789722100102X"
}