Significance of the contacting and no contacting thermoelectric power measurements applied to grit blasted medical Ti6Al4V

Thermoelectric assessment of laser peening induced effects on a metallic biomaterial Ti6Al4V

“…The TEP values decreased after the stress relaxation treatments at 595°C for 1h and at 710°C for 2h. Interestingly, annealing of the laser treated samples yields values that are similar to those in the as-machined condition, which correlates well with the absence of defects [11]. This means that only lattice defects were developed during processing and they are eliminated after annealing.…”

“…On laser treated sample, after the second stress release heat treatment (Figure 5b), the magnetic flux density of the base line is ~1.86 nT, which is actually larger than the signals produced by as-machined condition sample, which indicates that the background signature is due to residual stresses and/or axial texture caused by the laser peening process. Overall this study reveals that the non-contacting technique is more sensitive to the presence of residual stresses, whereas the contact technique is strongly influenced by the work hardening [11].…”

“…Thermoelectric power (TEP) measurements have recently gained a growing attention for the characterization of metallurgical properties in steels and other alloys. These measurements are sensitive to changes in the electronic structure of the material resulting from various metallurgical and mechanical processes [9][10][11][12][13][14]. The contacting thermoelectric technique analysis consists of measuring potential differences in the micro-volt range, generated by a small temperature difference along the sample.…”

“…Recently experimental results reported by Carreon et al [9][10][11] indicate that the stress-dependence of the thermoelectric power in metals produces sufficient contrast to detect and quantitatively characterize regions under compressive residual stress based on their thermoelectric contrast with respect to the surrounding intact material. The goal of this research work is to use two non-destructive thermoelectric techniques (NDTT), the non-contacting and contacting thermoelectric power measurements to sense the subsurface changes induced by laser peening in a metallic biomedical Ti-6Al-4V alloy.…”

Characterization of laser peening-induced effects on a biomedical Ti6Al4V alloy by thermoelectric means

“…Recently, experimental results reported by Carreon et al [10][11][12] indicate that the stress-dependence of the thermoelectric power (TEP) in metals produces sufficient contrast to detect and quantitatively characterize regions under compressive residual stress based on their thermoelectric contrast with respect to the surrounding intact material. Also, it was demonstrated that the thermoelectric method is entirely insensitive to surface topography while it is uniquely sensitive to subtle variations in thermoelectric properties, which are associated with the different material effects induced by different surface modification treatments.…”