Aluminum Bar Research Articles

Deep Learning-Based Subsurface Damage Localization Using Full-Field Surface Strains.

Structures in their service life are often damaged as a result of aging or extreme events such as earthquakes or storms. It is essential to detect damage in a timely fashion to ensure the safe operation of the structure. If left unchecked, subsurface damage (SSD) can cause significant internal damage and may result in premature structural failure. In this study, a Convolutional Neural Network (CNN) has been developed for SSD detection using surface strain measurements. The adopted network architecture is capable of pixel-level image segmentation, that is, it classifies each location of strain measurement as damaged or undamaged. The CNN which is fed full-field strain measurements as an input image of size 256 × 256 projects the SSD onto an output image of the same size. The data for network training is generated by numerical simulation of aluminum bars with different damage scenarios, including single damage and double damage cases at a random location, direction, length, and thickness. The trained network achieves an Intersection over Union (IoU) score of 0.790 for the validation set and 0.794 for the testing set. To check the applicability of the trained network on materials other than aluminum, testing is performed on a numerically generated steel dataset. The IoU score is 0.793, the same as the aluminum dataset, affirming the network's capability to apply to materials exhibiting a similar stress-strain relationship. To check the generalization potential of the network, it is tested on triple damage cases; the IoU score is found to be 0.764, suggesting that the network works well for unseen damage patterns as well. The network was also found to provide accurate predictions for real experimental data obtained from Strain Sensing Smart Skin (S4). This proves the efficacy of the network to work in real-life scenarios utilizing the full potential of the novel full-field strain sensing methods such as S4. The performance of the proposed network affirms that it can be used as a non-destructive testing method for subsurface crack detection and localization.

A FEM-Based Comparative Study of the Effect of Rotor Bar Designs on the Performance of Squirrel Cage Induction Motors

Induction motors (IM) are the most frequently used type of motor in the industry. The number of rotor slots, bar geometry, and conductivity of bar material have a strong impact on the torque profile and efficiency characteristics of induction motors. This study focused on investigating the effect of different rotor bar designs on motor performance by the finite element method (FEM). The IMs have been designed using the same stator core, winding, and core lengths. The total rotor bar cross-section areas are also fixed throughout all designs. In addition to the change in the number of rotor bars and geometry, the effect of copper and aluminum bar materials on motor performance was also investigated, both for single and double-layered squirrel-cage structures. The results of the study indicate that the starting torque of the motor in a 36/30-slot aluminum single-cage structure was obtained as 96.26 Nm, while the starting torque of a 36/46-slot aluminum double-cage structure was found to be 115.34 Nm. It is also found that the starting torque of the initial design can be increased by up to 19.82% by changing only the rotor bar numbers and material with the same stator and rotor size. The efficiency of the motors was determined as 86.6% for both designs. In addition to efficiency, the output torque ripple has been decreased to 2.63, which equals a 67.32% decrease in the ripple of the initial design. The improved design has an approximately 8 °C lower T2 due to better cooling performance as a result of a higher number of rotor slots.

Effects including photobiomodulation of galactomannan gel from Cassia grandis seeds in the healing process of second-degree burns

The epithelium recovery of skin-burned wounds has been currently achieved by several therapies, for example, hydrogel-based dressings and photobiomodulation therapy (PBMT). Thus, this work aimed to evaluate the healing activity of Cassia grandis seeds' galactomannan gel, associated or not with PBMT, in second-degree burns. Sixty male Wistar rats were assigned to four groups: Control (CG), Gel (GG), Laser/PBMT (LG), and Laser+Gel (GLG). Burns were made with an aluminum bar (90 °C), and submitted to clinical observations diary and area measurements at specific days. Microscopic analysis was based on histological criteria. The results showed that GG, LG, and GLG had a higher contraction rate (p < 0.05) than CG on the 14th experimental day, not differing from each other (∼95 %). At 21 days, all groups showed complete contraction (p > 0.05). Considering the histological results, LG and GLG showed excellent pro-wound healing properties after 14 days; at 21 days, all groups showed wound recovery compared to previous days. In view of the macroscopic and microscopic observations, the isolated treatments (Gel or Laser) effectively accelerated healing; however, the association (Laser+Gel) promoted re-epithelialization and stromal remodeling with better evolution of epithelium recovery due to the positive synergistic effect, thus emerging as a promising therapeutic alternative in the repair of burns.

A Highly Sensitive 3D Resonator Sensor for Fluid Measurement.

Planar sub-wavelength resonators have been used for sensing applications, but different types of resonators have different advantages and disadvantages. The split ring resonator (SRR) has a smaller sensing region and is suitable for microfluidic applications, but the sensitivity can be limited. Meanwhile, the complementary electric-LC resonator (CELCR) has a larger sensing region and higher sensitivity, but the topology cannot be easily designed to reduce the sensing region. In this work, we propose a new design that combines the advantages of both SRR and CELCR by incorporating metallic bars in a trapezoid-shaped resonator (TSR). The trapezoid shape allows for the sensing region to be reduced, while the metallic bars enhance the electric field in the sensing region, resulting in higher sensitivity. Numerical simulations were used to design and evaluate the sensor. For validation, the sensor was fabricated using PCB technology with aluminum bars and tested on dielectric fluids. The results showed that the proposed sensor provides appreciably enhanced sensitivity in comparison to earlier sensors.

Seismic failure probability analysis of slopes via stochastic material point method

Earthquakes, an important factor in inducing landslides, usually have great randomness. Moreover, landslides are investigated as large deformations, and traditional grid-based methods encounter mesh distortions when dealing with such problems. In this context, the spectral expression method and random functions are introduced to generate stochastic ground motions, and the material point method is adopted to perform probabilistic slope analysis. First, the dry aluminum bar collapse test and the Chiu-fen-erh-shan landslide were simulated to verify the effectiveness of this improved procedure. Then, three typical stochastic ground motions were selected to investigate the effects of material parameters (internal friction angle and cohesion) and slope geometry (slope inclination and height) on the sliding distance of the slope. Finally, the uncertainty of ground motions was taken into account when conducting the probabilistic analysis of earthquake-induced landslides. The results demonstrate that the sliding distance of slopes varies with earthquake action, exhibiting certain randomness, particularly in strong earthquakes. In addition, slope geometry influences sliding distances more than material parameters, and slope geometry should be the prior consideration for slope prevention and mitigation.

764 Comparison of Topical Silver Sulfadiazine and Triple Antibiotic Ointment in a Porcine PT Burn Model

Abstract Introduction The standard of care for partial thickness burns is topical antibiotics or occlusive dressing. Silver Sulfadiazine (SSD) emerged at a time of burn wound infection and sepsis prevalence and is now the most used topical worldwide. Despite its antimicrobial benefits, SSD has been shown to inhibit keratinocytes and there is concern that it might delay wound healing. This study compared time to complete wound closure and reepithelialization in partial thickness porcine burns treated with SSD, triple antibiotics ointment or petrolatum ointment Methods We created 21 deep partial thickness (DPT) burns per animal on the backs and flanks of 3 anesthetized domesticated pigs (30-35 kg) using an established vertical progression model (aluminum bar preheated to 80° C for 20s). In each pig, burns were randomly assigned SSD, triple antibiotic ointment, or petrolatum ointment (in a 1:1:1 ratio) applied daily for two weeks followed by twice weekly for another 2 weeks. Healing progression was measured by wound digital photography and punch biopsies to assess gross wound closure, reepithelization and scar depth respectively. Results The median (IQR) days to complete wound closure were 17 (17-21), 17 (14-21), and 21 (17-21) for wounds treated with SSD, petrolatum and triple antibiotic ointment respectively (p=0.06). The mean percentage of wound reepithelization at days 10, 14, 17, 21, and 28 for wounds treated with, SSD, petrolatum, and triple antibiotic ointment were 10%±20 vs. 8%±14 vs. 3%±12 (p=0.34), 45%±49 vs. 37%±44 vs. 48%±42 (p=0.74), 82%±38 vs. 86%±20 vs. 90%±27 (p=0.7), 74%±38 vs. 65%±50 vs. 93%±16 (p=0.049), and 92%±17 vs. 91%±28 vs. 98%±5 (p=0.4). The mean scar depth was 3.9 (1.1), 4.2 (0.9), and 3.4 (0.9) mm for wounds treated with SSD, petrolatum, and triple antibiotic ointment respectively (p=0.07). RMANOVA analysis showed significant change over time (p&amp;lt; 0.001) and a near significant difference between groups (p=0.054). On macroscopic analysis, appreciable pseudoeschar formation and erythematous allergic reactions were identified on wounds treated with SSD and triple antibiotic ointment respectively. Conclusions No significant differences in wound healing were found between groups in this porcine DPT burn model. SSD did not delay closure. Hypersensitivity to topical triple antibiotics was common. Applicability of Research to Practice This study provides insight into the topical ointment standard of care for burns and helps establish the standard comparator topical treatment for future preclinical and clinical studies.

Structure and strain state of aluminum bars at the initial phase of extrusion

The structure of insufficiently deformed areas at the non-steady phase of extrusion was studied. The tests at Kamensk Uralsky Metallurgical Works using a 120 MN press and 800 mm dia. container, in order to extrude a 355.6 mm dia. Bar was performed. The bar material is the Al–Mg–Si AD33 aluminum alloy (GOST 4784), similar to ASTM 6061. The percentage reduction was 80 %, and the reduction ratio was 5.06. After that, the macrostructure, microstructure, and average grain size along the radius, mechanical properties at room and elevated temperatures were investigated. It was found that the extruded bar macrostructure is fine-grained, homogeneous, and dense, with no nonmetallic or intermetallic inclusions. The cross-section contained several structures. The central part is weakly deformed preserving the dendritic cell structure inherited from the casting. At the circumference, a streaked structure is formed. Its components are crushed and uniformly distributed. We measured the strength at elevated temperatures and compared the results to the data available in the literature. The tested material strength almost doubled, thus indicating its incomplete softening. The ductility was also performed. The DEFORM-2D software, in order to simulate the low reduction of extrusion was used. The metal at the circumference is exposed to a greater strain from the extrusion beginning. A step-by-step analysis indicated that at the first step, the strain is localized near the die hole. In the second step, a rigid area is formed in the vicinity of the die/container liner interface. The circumference layer of metal with a 1.75–2.00 reduction of area is formed. At the bar center, this range is 0.75–1.00 (half of the circumference value). In the third step, the circumference layer with an elevated strain has a wedge-like shape. In the fourth step, the circumference layer (with elevated strain) has an equal thickness along the extrusion axis. This indicates the steady phase. The plastic strain at the bar front end is higher at the circumference than in the center. This confirms the structural analysis results. They show that the central part of the bar may retain its cast structure, while the circumference is deformed. If the bar central part is required to have some specific properties, the bar has to undergo another manufacturing operation to increase the accumulated strain. Re-extrusion processes the areas insufficiently deformed during the first extrusion.

Improving the technology of nitridation by the electro-spark alloying method

The work shows studies aimed at developing methods for protection of structural steels on the example of steels 20 and 40, from wear, using the electricity spark alloying (ESA), by applying the nitrogen-like mixture on the treated surface with subsequent vanity of steel electrode appropriate to the material of the workpiece. To increase the thickness of the surface layer and the best adhesion of the coating is offered in front of the ESA electrode-tools made of steel of the corresponding brand, to form a mold of aluminum, using an electrode from the aluminum bar of the brand of blood pressure. Metrolographic studies were performed and the distribution of microtrandomness in the coating. Studies have shown that nitrogen -containing coatings consist of a "white" layer ", which smoothly goes into the diffusion zone and base metal. The obtained coatings have the highest thickness of "white layer" 110-130 microns. The results of the study of the micro-hardness of the obtained nitrogen-containing coatings indicate an increase in hardness to 9700-9910 MPa. The phase composition of nitrogen coatings is represented by a alloy solid and cubic iron nitride, aluminum dissolves in nitride and ferrite. The considered methods of application of nitrogen -containing coatings can be used to strengthen the surface of responsible parts and elements of pumping and compressor equipment: end surfaces of rings, for protective bushings; piston machines, mechanisms that have increased wear of the product, etc. Keywords: electro-spark alloying, microstructure, nitriding, steel, phase analysis.

Cyclic load tests and finite element modeling of self-centering hollow-core FRP-concrete-steel bridge columns

This paper presents experimental and numerical investigations of the seismic performance of a novel self-centering (SC) hollow-core (HC) fiber-reinforced polymer (FRP)-concrete-steel (SC-HC-FCS) bridge column. This new structure is fabricated by mounting external energy dissipators (ED) and applying unbonded post-tensioned (PT) basalt FRP (BFRP) tendon to the conventional HC-FCS column that consists of an outer FRP tube and an inner steel tube, with the space between filled with concrete. The SC-HC-FCS column combines the advantages of accelerated bridge construction and self-centering. The effects of the initial prestress force values and the configuration of the energy-dissipated aluminum bar on the column performance are studied. Based on the experimental and numerical results, it is found that the proposed SC-HC-FCS column shows adequate self-centering and energy dissipation capacities. However, it is required to properly select the configuration and material properties of the aluminum bar as energy dissipators to further refine the seismic resistance of the SC-HC-FCS column.

Could convulsive body shuddering of a white shark near a shark cage be an element of a threat display?

Abstract In this short note, we describe the convulsive body shuddering of a white shark as it approached two large metallic shark cages, each with multiple divers standing within them. When animals feel threatened, they experience conflicting instincts — one is to escape and another is to fight. In this situation, they do not always fight but often perform an agonistic, or aggressive display. Having arrived at the source of an olfactory corridor, this white shark was confronted with highly visible cages made with aluminium bars. The divers use hookah air hoses to breathe, and were therefore releasing bubbles, which reflect light and generate sounds as they oscillate toward the surface. The photographers may also have been taking pictures of the shark with their flash-bulb equipped cameras, which produce a sudden disruptive flash of irradiance. The shark’s behaviour is illustrated with a series of video frames as he approaches the cage. The body of the shark shutters convulsively and he opens his mouth, keeping it open for a prolonged period of 2.8 s as he passes close to the cage, while (1) depressing his pectoral fins, (2) hunching his back, (3) keeping his caudal fin held at right angle to the axis of view to increase his apparent size, and (4) shaking his body with spasmodic oscillations. The shark appears frightened, and hence may perform the display to discourage any aggression directed at him by the cage with humans emitting a panoply of frightening stimuli. Alternative explanations of the motivation behind this behaviour are also discussed. We hope that it will lead other scientists to look for this behaviour when observing the behaviour of white sharks from a cage, so they can provide further evidence shedding light upon the shark’s motivation for performing this conspicuous behaviour.

A Study on a Design Considering the Transient State of a Line-Start Permanent Magnet Synchronous Motor Satisfying the Requirements of the IE4 Efficiency Class

In this paper, the transient state analysis of a Line-Start Permanent Magnet Synchronous Motor (LSPMSM) and the optimum design for high efficiency were studied. In the case of an LSPMSM, aluminum bars and permanent magnets are inserted in the rotor. Since it has aluminum bars, it can be directly started on-line without closed-loop control at the time of starting, like an induction motor. Furthermore, once driven, it rotates at a synchronous speed due to the permanent magnets in the steady state. Theoretically, since the rotor bars have no induced current, copper loss does not occur in the rotor bars. Further, because of the inserted permanent magnets, an LSPMSM has a higher power density than an induction motor with the same output power. However, since it is driven directly on-line, the transient state is longer than that of a synchronous motor driven by an inverter. Therefore, it is important to analyze the characteristics of the transient state depending on the rotor shape in the LSPMSM design. In this study, an LSPMSM that has the same outer diameter of a 7.5 kW IE3 efficiency class induction motor currently used for the industry was designed. The optimal design of the motor was designed using Finite-Element Analysis (FEA) and Design of Experiment (D.O.E). In the design process, the velocity ripple was minimized in the transient state, and the steady state was quickly reached. Finally, the efficiency of the motor satisfies the requirements of the IE4 efficiency class, an efficiency standard described in IEC 60034-30, which is an international standard.

Miniature Beryllium Split-Hopkinson Pressure Bars for Extending the Range of Achievable Strain-Rates

Conventional Split Hopkinson Pressure Bars (SHPB) or “Kolsky” bars are often used for determining the high-rate compressive yield and failure strength of materials. However, for experiments generating very high strain-rates (&gt;103/s) miniaturization of the setup is often required for minimizing the effects of elastic wave dispersion in order to enable the inference of decreasingly short loading events from the data. Miniature aluminum and steel bars are often sufficient for meeting these requirements. However, for high enough strain-rates, miniaturization of steel or aluminum Kolsky bars may require prohibitively small diameter bars and test specimens that could become inappropriate for inferring representative properties of materials with large grain size relative to the test specimen size. The use of a beryllium Kolsky bar setup is expected to enable high rates to be accessible with larger diameter bars/specimen combinations due to the inherent physical properties of beryllium, which are expected to minimize the effects of elastic wave dispersion. For this reason, a series of beryllium Kolsky bars have been developed, and, in this paper, the dispersion characteristics of these bars are measured and compare the data with those of similarly sized 7075-T6 aluminum and C350 maraging steel. The results, which agree well with the theory, show no appreciable frequency dependence of the elastic wavespeed in the data from the beryllium bars, demonstrating its advantage over aluminum and steel in application to Kolsky bars.

Self-Centering Prestressed Concrete Pier Considering the Effect of Vertical Earthquake Motions with External Aluminum Dissipators

A prototype self-centering prestressedconcrete (SCPC) bridge pier andconventional reinforced concrete (RC) pier with similar backbone curves are designed and modeled. The objective of this study is to investigate the seismic performance of the SCPC bridge pier considering the effect of vertical earthquake ground motions. Under a severe vertical earthquake motion, the RC pier damage is much greater than the SCPC pier. The SCPC bridge pier shows a great capability in reducing residual drift at the top of the structure, therefore, the probability of bridge survival is increased. In this study, the external aluminum bars were used to reduce the seismic energy impacts on the bridge pier structure. In addition, the averages of the maximum and residual drifts of bridge piers under a set of 20 earthquake ground motion records impact with different vertical-to-horizontal peak acceleration ratios on the bridge seismic response are presented. The results are compared with the case of horizontal-only excitations, to clarify the effect of the vertical earthquake on the SCPC and RC bridge pier. Hence, the designers can find good solutions for structures in earthquakes resistance.

Development of a device that generates a temperature gradient in a microtiter plate for microbial culture.

Although temperature is a fundamental parameter in biology, testing various temperature conditions simultaneously is often difficult. In the present study, we developed a device for generating a temperature gradient in arrays of wells on a microtiter plate. This device consists of a pair of Peltier elements and temperature sensors placed on both ends of a flat aluminum bar to generate a linear temperature gradient. The device loads a microtiter plate at the center of the aluminum bar and transfers the temperature gradient to the bottom of the wells in the plate. This device successfully maintained a temperature gradient of 38.2 to 43.1°C on the horizontal axis of a 96-well microtiter plate in an incubator at 31°C. Furthermore, using this device, we demonstrated a laboratory evolution experiment of Escherichia coli, which was selected on the basis of its ability to grow at high temperatures. The developed device also facilitates a two-dimensional assay to determine the effects of temperature and drug concentrations on cellular growth.

Calibrating a double aluminium bar with electrotensometric strain gauge attached

The transducers which are used for measuring force or weight are also called load cells. Most of those transducers use strain gauges to measure the applied force. In this paper, a calibration of a double aluminium bar with strain gauges attached is conducted in order to determine the major sources of error in the measurement process. The authors explain the entire process of calibration for a single load cell. The purpose is to determine the main measurement errors. The sensor was calibrated at maximum of 10 kg and loading were made by manual application of weights. The results of calibration reveal a very small hysteresis and linearity error which makes the sensor a reliable choice to measure force, weight, or load.

Spider-based FOPID controller design for temperature control in aluminium extrusion process

Abstract Based on the exit temperature in the aluminium extrusion process, the quality of the aluminium bars is obtained in the industries. Control of temperature plays a significant role to obtain the quality of the aluminium bars or rods. Problems are still encountered in the design of proper temperature control schemes in the industries. A new control scheme is presented here, to address the temperature control in the aluminium extrusion process. Spider-based fractional-order PID controller scheme is simulated for the aluminium extrusion plant using MATLAB and its toolbox. It gives the improved result for reducing the time delay, rise time and settling time in the process. Integral square error performance criteria are considered an objective function. The minimization of objective function gives good results. Comparisons of the presented control scheme with the conventional control methods are presented.

Evaluating interlayer gaps in friction stir spot welds for rapid tooling applications

Potential for a rapid hybrid additive/subtractive manufacturing technique capable of generating large aluminum components with deep geometrical features exists if, for example, layers of aluminum plates can be deposited and held in place using friction stir welding followed by machining. However, when plates of aluminum are friction stir spot welded together, adjacent material can deform causing a gap between layers. This research investigates how friction stir tool geometry affects the formation of interlayer gaps and the lap shear strength of the weld. For this purpose, residual stresses and microhardness were measured to characterize the weld formation process. While friction stir welding of 6061 aluminum bar stock was carried out on a machining center with three different pin diameters (5.7, 6.4, 7.0 mm) and two pin lengths (8.9, 10.2 mm). In general, outcomes of the research show that lap shear strength trends upward with increasing pin diameter but does not show a strong relation to the pin length. Interlayer gap size increases with pin length, but does not show a clear trend with pin diameter. Compressive residual stresses were observed on the weld shoulder with no significant variations occurring among the studied stir tool geometries. No significant change was measured in microhardness values when the pin length or shoulder diameter were changed, suggesting that the increase in lap shear strength is due to a change in weld cross-section instead of a material property change. This research will guide friction stir tool geometry selection for this hybrid manufacturing process and can be applied more broadly to any application where material deformation around a weld is undesirable.

Progress on developing a new SAE damping standard for the ground vehicle industry

With the emphasis in lightweighting of vehicle body structures, body panel vibration and structure-borne noise are big concerns to sound package engineers. Damping materials are used to mitigate these issues. As aluminum and different composite materials are used to make lightweight vehicle body panels, a damped panel using these materials cannot be used in Oberst bar damping tests which uses a non-contacting transducer. To address this situation, SAE's Acoustical Materials Committee is developing a new damping standard (SAE J3130) based on the mechanical impedance measurement method, also called the CenterPoint method. The committee is currently conducting a round robin study that includes different types of damping materials and different types of vibrating bars, including steel, aluminum, and glass bars. This paper discusses the status of the round robin testing. It emphasizes the importance of data analysis using h statistic and k statistic, where h statistic checks the difference between means and k statistic checks the difference between variances. The paper illustrates some case studies based on the work done so far.

Optimization of Process Parameters in CNC Turning of Copper and Aluminium Alloy Using Taguchi Approach

Abstract: This paper manages the optimization level comparison of the metal copper (Cu) and aluminium (Al) bar by utilizing the Taguchi strategy with the orthogonal array (L27) powerful plan. The yield of the improvement is from the turning of the copper and aluminium bar utilizing a CNC machine. Taguchi strategy is an adaptable strong plan procedure that is utilized in numerous ventures known for its high interaction quality, upkeep and advancing the nature of the item soundness. It is an incredible and proficient strategy for upgrading the exhibition of different mechanical assembling measures. The machining boundaries (speed, feed rate, depth of cut) of both the materials copper and aluminium is taken as a comparison for accomplishing the base surface roughness by utilizing the Taguchi strategy for DOE and ANOVA to accomplish the optimization level for the best quality item for minimal price in the manufacturing processes. Three level of parametric esteems have been picked as input parameters to get critical ideal yield results for the materials. In the wake of examining the information and ascertaining the signal to noise ratio (S/N) the last ideal levels of each input parameters are acquired to look at the best outcomes. Keywords: Surface roughness, Taguchi method, CNC turning, Optimization.

Interlaboratory Reproducibility of Contour Method Data in a High Strength Aluminum Alloy

BackgroundThe contour method for residual stress measurement has seen significant development, but an experimental reproducibility study utilizing physical samples has not been published.ObjectiveA double-blind reproducibly study is reported, having scope beginning with EDM cutting and ending with residual stress calculation.MethodsA reinforced I-beam sample geometry is identified for its unique residual stress profile when extracted from residual stress bearing quenched aluminum bar (7050-T74). Contour measurements are prescribed on a midplane of symmetry with dimensions 24.0 mm by 50.0 mm. Fourteen identically prepared samples are fabricated from a single long bar with well characterized and uniform residual stress. Five samples throughout the bar are identified for planning measurements to validate sample uniformity and overall suitability of the residual stress field. The planning measurements employ a range of techniques: contour method, neutron diffraction, and hole-drilling. Eight samples are distributed to an international group of participants to execute their standard measurement practice. A double-blind process is followed to provide anonymity.ResultsResults are provided by eight participants: six being self-similar and two being quite different, the latter set aside as outliers. An average residual stress field is established from non-outlying results and the spatial distribution of reproducibility standard deviation is determined. The average stress field ranges from -60 to 70 MPa and the reproducibility standard deviation averages 8.1 MPa on the measurement plane. The average reproducibility standard deviation is about 3 × larger for points within 1.0 mm of plane boundaries (17.6 MPa) than for the remaining points (6.1 MPa).ConclusionsReproducibility standard deviation (among different labs) for contour method residual stress measurement is found to be very similar to repeatability standard deviation (in a single lab) reported in prior work. The reproducibility observed here, for the entire measurement process, is also similar to that found in a prior reproducibility study limited to contour method data analysis.