PSI - Issue 43

Pavel Doubek et al. / Procedia Structural Integrity 43 (2023) 101–106

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Pavel Doubek et al./ Structural Integrity Procedia 00 (2022) 000 – 000

It was assumed that the Poisson’s ratio and the Young’s modulus of the interp hase are not affected by heat treatment conditions. The influence of the changes in chemical composition over the Poisson’s ratio was determined by a linear transition depending on a distance to the starting point of the measurement. The Young ’ s modulus of a pa rticular layer is then calculated using equations (2), see e.g. Haušild et al. (2016). = 2 1 ∙ √ ∙ ℎ ; = (1 − 2 ) ∙ ( 1 − 1− 2 ) −1 were = (2 ∙ ℎ ∙ 68°) 2 (2) where E r – relative modulus of elasticity; E s – modulus of elasticity of the measured sample; E i – modulus of elasticity of the indenter; A c – the area of the perpendicular projection of the impression; ν s – Poisson ’ s ratio of the measured sample, ν i – Poisson ’ s ratio of the indenter,  − correction coefficient depending on the type of the indenter. The parameters used within a calculation of E r and E S are given in Tab. 4.

Table 4. Properties of the set-up, and materials used for the calculation of Young’s modulus E r and E S . Applied load Vickers HV 0.5 Young’s modulus of the diamond indenter Poisson's ratio of the diamond indenter Poisson's ratio of the interface between Metco 51NS and S960

Poisson's ratio of the interface between Rockit 401 and S960

Correction coefficient for Vickers

F [N]

E i [GPa]

ν i [ – ] 0.20

ν 1 [ – ]

ν 2 [ – ]

 [ – ] 1.024

4.9

840

0.27 ÷ 0.32

0.22 ÷ 0.27

3. Results and discussion Three samples for each type of surface layer – aluminum bronze, and hard chrome – were measured and processed. In this paper, the results of one representative sample for each of them are presented. In Tab. 3 and Tab. 4. there are summarized the fundamental measured values and results of the calculations. The number of measurements corresponds to the thickness of the cladded layer after machining. Table 3. Measured values of Vickers hardness and the results of Young‘ s modulus for the S960 bi-material interface and Metco 51NS. Parameter Unit Value to the surface ← Interface → Distance to start point mm -2 -1.8 -1.6 -1.4 -1.2 -1.0 -0.8 -0.6 -0.4 -0.2 0.2 Hardness HV 0.5, set 1 – 174 187 186 168 179 190 200 202 218 232 337 Hardness HV 0.5, set 2 – 190 186 183 189 184 178 191 218 220 219 346 Young’s modulus E S1 , set 1 GPa 124.8 131.2 131.1 123.9 129.9 133.6 138.4 139.8 146.8 152.9 192.7 Young’s modulus E S2 , set 2 GPa 132.5 131.7 130.6 133.5 132.0 130.0 135.8 147.2 148.4 148.4 196.8 346 Young’s modulus E S1 , set 1 GPa 193.1 189.1 195.4 179.5 195.7 199.3 200.1 202.5 202.5 Young’s modulus E S2 , set 2 GPa 197.1 197.3 182.4 188.9 199.1 200.6 200.4 202.7 202.5 Table 4. Measured values of Vickers hardness and the results of Young‘s modulus for the S960 bi-material interface and Rockit 401. Parameter Unit Value to the surface ← Interface → Distance to start point mm -1.8 -1.6 -1.4 -1.2 -1.0 -0.8 -0.6 -0.4 -0.2 0.2 0.4 Hardness HV 0.5, set 1 – 624 604 648 599 591 610 517 544 508 346 328 Hardness HV 0.5, set 2 – 648 624 633 588 544 539 500 525 506 320 350 Young’s modulus E S1 , set 1 GPa 112.3 122.1 140.0 146.2 157.8 174.0 169:6 187.7 192.5 162.3 188.3 Young’s modulus E S2 , set 2 GPa 140.2 111.7 124.7 131.4 137.1 148.0 152.9 169.4 177.5 144.0 161.1 Parameter Unit mm Value Distance to start point Hardness HV 0.5, set 1 Hardness HV 0.5, set 2 0.4 337 345 0.6 324 344 0.8 339 301 1.0 294 317 1.2 336 344 1.4 344 346 1.6 344 344 1.8 349 349 2.0 349 – –

Parameter

Unit mm

Value

Distance to start point Hardness HV 0.5, set 1 Hardness HV 0.5, set 2

0.6 366 350

0.8 349 345

1.0 344 346

1.2 344 350

1.4 349 349

1.6 344

– –

346 Young’s modulus E S1 , set 1 GPa 193.7 202.5 200.1 200.0 202.5 200.0 Young’s modulus E S2 , set 2 GPa 171.1 180.0 190.6 202.5 202.5 202.5