Development, Characterisation and High-Temperature Suitability of Thin-Film Strain Gauges Directly Deposited with a New Sputter Coating System

Klaas, Daniel; Ottermann, Rico; Dencker, Folke; Wurz, Marc Christopher

doi:10.3390/s20113294

Cited by 18 publications

(11 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For this whole manufacturing process, the Institute of Micro Production Technology of the Leibniz University Hannover developed a patented coating system [26][27][28]. Manufactured strain gauge sensors were able to withstand maximum operation temperatures up to 400 °C and showed higher temperature compensation capability compared to common sensors [1,29]. Thin-film-based sensors have been integrated into metal tools to measure process parameters in industrial processes such as sheet temperature during mold hardening or material flow of the metal sheet during deep drawing [30,31].…”

Section: Strain and Temperature Measurements Using Directly Deposited...mentioning

confidence: 99%

“…An important parameter for directly deposited strain gauges is the temperature coefficient of resistance (TCR) which indicates the resistance change due to temperature according to equation (1). The lower the TCR, the lower is the temperature impact on the sensor signal resulting in lower measurement errors.…”

Section: Temperature Coefficient Of Resistancementioning

confidence: 99%

“…Thus, perforating of polymerfilm and glue during zero-point setting can be omitted. Due to the polymer-free sensor system, a higher temperature resilience up to at least 400 °C compared to polymer foil-based is given [1]. In combination with the minimal sensor thickness, new areas of interest can be addressed by directly deposited sensors.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Residual Stresses from Incremental Hole Drilling Using Directly Deposited Thin Film Strain Gauges

et al. 2022

View full text Add to dashboard Cite

Background Commonly, polymer foil-based strain gauges are used for the incremental hole drilling method to obtain residual stress depth profiles. These polymer foil-based strain gauges are prone to errors due to application by glue. For example zero depth setting is thus often erroneous due to necessary removal of polymer foil and glue. This is resulting in wrong use of the calibration coefficients and depth resolution and thus leading to wrong calculations of the obtained residual stress depth profiles. Additionally common polymer foil-based sensors are limited in their application regarding e.g. exposure to high temperatures. Objective This paper aims at a first step into the qualification of directly deposited thin film strain gauges for use with the incremental hole drilling method. With the directly deposited sensors, uncertainties regarding the determination of calibration coefficients and zero depth setting due to the absence of glue can be reduced to a minimum. Additionally, new areas of interest such as the investigation of thermally sprayed metallic layers can be addressed by the sensors due to their higher temperature resilience and their component inherent minimal thickness. Methods For the first time, different layouts of directly deposited thin film strain gauges for residual stress measurements were manufactured on a stainless steel specimen. Strain measurements during incremental hole drilling using a bespoke hole drilling device were conducted. Residual stress depth profiles were calculated using the Integral method of the ASTM E837 standard. Afterwards, strain measurements with conventional polymer foil-based strain gauges during incremental hole drilling were conducted and residual stress depth profiles were calculated accordingly. Finally the obtained profiles were compared regarding characteristic values. Results The residual stress depth profiles obtained from directly deposited strain gauges generally match the ones obtained from conventional polymer foil based strain gauges. With the novel strain gauges, zero depth setting is simplified due to the absence of glue and polymer foil. With the direct deposition, a wide variety of rosette designs is possible, enabling a more detailed evaluation of the strain field around the drilled hole. Conclusions The comparative analysis of the obtained residual stress depth profiles shows the general feasibility of directly deposited strain gauges for residual stress measurements. Detailed investigations on uncertainty sources are still necessary.

show abstract

Section: Strain and Temperature Measurements Using Directly Deposited...mentioning

confidence: 99%

Section: Temperature Coefficient Of Resistancementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Residual Stresses from Incremental Hole Drilling Using Directly Deposited Thin Film Strain Gauges

et al. 2022

View full text Add to dashboard Cite

show abstract

“…For instance, Constantan and NiCR 80/20 alloys, which are commonly used strain gauges, have TCR values of 40 and 85 ppm/°C for bulk materials, respectively. 6 On the other hand, silicon, germanium, and amorphous carbon have TCR values of −0.075, −0.048, and −0.0005 ppm/°C, respectively. Conventionally, metals or silicon piezoresistors are used as strain gauges.…”

Section: Introductionmentioning

confidence: 99%

SiOC-Based Strain Gauge with Ultrahigh Piezoresistivity at High Temperatures

Ricohermoso

Solano‐Arana

Fasel

et al. 2023

ACS Appl. Eng. Mater.

View full text Add to dashboard Cite

The nonlinear response of strain gauges at high temperatures has restricted their applications despite their highprecision and real-time measurement capability. This work addresses this limitation by utilizing the easy preparative access and versatility of silicon oxycarbide-based (SiOC) thin films as strain gauges offering outstanding high-temperature robustness and giant piezoresistive response. The sensitivity of the strain gauge is assessed with continuous cyclic loads, tensile and compressive, resulting in gauge factors of ca. 2000−5000. The linearity of the response is preserved up to 700 °C with a shift in the electrical response occurring at temperatures beyond 500 °C, switching the SiOC film from semiconducting to conducting behavior. This change causes a drop in the gauge factor of the SiOC-based thin films; nevertheless, it is still significantly higher than that of metallic and Si-based commercial strain gauges. Notably, the studied thin films can regulate the effect of temperature enabling them to be a highly sensitive device with good reversibility and replicability in high-temperature environments. Furthermore, the electrical shift at 460 °C broadens the application of the SiOC film as a currentlimiting device and temperature sensor.

show abstract

“…Metals, semiconductors, and ceramics can be used as sensitive materials for thin-film strain gauges. However, so far, only a few high-temperature thin-film strain gauge materials have been reported, such as Ni80Cr20 [ 7 , 8 ], PdCr [ 9 ], TAN-Cu [ 10 ], and TiAlN [ 11 ], but the oxidation resistance is poor and the electrical performance decreases at high temperatures. Ni80Cr20 and TiAlN are used at temperatures below 600 °C.…”

Section: Introductionmentioning

confidence: 99%

Development of High-Temperature Wire-Grid Thin Film Strain Gauges

Cui

Zhang³

et al. 2022

Sensors

View full text Add to dashboard Cite

Aero-engine turbine stator blades are often used in harsh environments with high temperatures and high pressure and are prone to fatigue fractures. Real-time and accurate monitoring of blade surface stress and strain is critical to ensure safe operation. In this study, thin-film strain gauges (TFSGs) that can be used in high-temperature environments above 1000 °C were designed and fabricated using a PtRh6 thin film as the sensitive material. The hysteresis effect of the stress transfer upon establishing a thermo-mechanical coupling finite element model of the Inconel718 high-temperature nickel-based alloy equal-strength beam PtRh6 TFSGs was analyzed and the optimal combination of thin-film thickness and longitudinal grid length of wire-grid TFSGs was determined. In order to solve the problem of high-temperature insulation, the insulating properties of a single-layer Al2O3 insulating film, a single-layer ZrO2 insulating film, a double-layer Al2O3/ZrO2 composite insulating film, and a four-layer Al2O3/ZrO2/Al2O3/ZrO2 composite insulating film at high temperature were compared and studied using scanning electron microscopy to analyze the microscopic morphology and composition of the four insulating film structures. The results showed that the four-layer Al2O3/ZrO2/Al2O3/ZrO2 composite insulating film had the best insulating properties at high temperatures. On this basis, an Al2O3/ZrO2/Al2O3/ZrO2 composite insulating film, PtRh6 sensitive layer, and Al2O3 protective film were sequentially deposited on a high-temperature nickel-based alloy equal-strength beam using DC pulsed magnetron sputtering technology to obtain an Inconel718 high-temperature nickel-based alloy equal-strength beam PtRh6 TFSG. Its gauge factor (GF) and temperature coefficient of resistance (TCR) were calibrated, and the results showed that the sensor could be used in harsh environments of 1000 °C. The above results provide new ideas for measuring stress and strain in aerospace under high-temperature and high-pressure environments.

show abstract

Development, Characterisation and High-Temperature Suitability of Thin-Film Strain Gauges Directly Deposited with a New Sputter Coating System

Cited by 18 publications

References 21 publications

Residual Stresses from Incremental Hole Drilling Using Directly Deposited Thin Film Strain Gauges

Residual Stresses from Incremental Hole Drilling Using Directly Deposited Thin Film Strain Gauges

SiOC-Based Strain Gauge with Ultrahigh Piezoresistivity at High Temperatures

Development of High-Temperature Wire-Grid Thin Film Strain Gauges

Contact Info

Product

Resources

About