Extreme High-temperature Environments Research Articles

Gas-Phase Preparation of Silyl Cyanide (SiH3CN) via a Radical Substitution Mechanism.

The silyl cyanide (SiH3CN) molecule, the simplest representative of a fully saturated silacyanide, was prepared in the gas phase under single-collision conditions via a radical substitution mechanism. The chemical dynamics were direct and revealed a pronounced backward scattering as a consequence of a transition state with a pentacoordinated silicon atom and almost colinear geometry of the attacking cyano radical and leaving hydrogen. Compared to the isovalent cyano (CN)-methane (CH4) system, the CN-SiH4 system dramatically reduces the energy of the transition state to silyl cyanide by nearly 100 kJ mol-1, which reveals a profound effect on the chemical bonding and reaction mechanism. In extreme high-temperature environments including circumstellar envelopes of IRC +10216, this versatile radical substitution mechanism may synthesize organosilicon molecules via reactions of silane with doublet radicals. Overall, this study provides rare insights into the exotic reaction mechanisms of main-group XIV elements in extreme environments and affords deeper insights into fundamental molecular mass growth processes involving silicon in our universe.

Intermetallic compound transformation and mechanical strength of Ni–Sn transient liquid phase sinter-bonded joints in an extreme high-temperature environment

Intermetallic compound transformation and mechanical strength of Ni–Sn transient liquid phase sinter-bonded joints in an extreme high-temperature environment

Designing Polyurethane Solid Polymer Electrolytes for High-Temperature Lithium Metal Batteries

Potentially high-performance lithium metal cells in extreme high-temperature electrochemical environments is a challenging but attractive battery concept that requires stable and robust electrolytes to avoid severely limiting lifetimes of the cells. Here, the properties of tailored polyester and polycarbonate diols as the soft segments in polyurethanes are investigated and electrochemically evaluated for use as solid polymer electrolytes in lithium metal batteries. The polyurethanes demonstrate high mechanical stability against deformation at low flow rates and moreover at temperatures up above 100 °C, enabled by the hard urethane segments. The results further indicate transferrable ion transport properties of the pure polymers when incorporated as the soft segments in the polyurethanes, offering designing opportunities of the polyurethane by tuning the soft segment ratio and composition. Long-term electrochemical cycling of polyurethane-containing cells in lithium metal batteries at 80 °C proves the stability at elevated temperatures as well as the compatibility with lithium metal with stable cycling maintained after 2000 cycles.

Development of Sapphire Optical Temperature Sensing System Used in Harsh Environment Sensing

A sapphire optical fiber blackbody radiation sensor based on the high temperature multilayer structure of wolfram and aluminum oxide has been developed. Through the analysis of Planck’s law, the linear relationship between the temperature and the square root of the voltage is theoretically deduced. Radio frequency magnetron sputtering method is used to sputter and deposit high-temperature wolfram metal film and aluminum oxide film on sapphire fiber. In order to meet the needs of real-time temperature measurement, an online acquisition system of optical signals is designed to complete the demodulation and storage of signals. The high-temperature experiment results show that the temperature response sensitivity is 0.00113V1/2/℃ between 300℃ and 1750℃, and it can work stably for more than 10 hours. The sensor is calibrated in the metrology institute where a maximum quoted error of 0.84% within a range between 900 ℃ and 1600℃ is proved. Compared with the traditional high temperature measurement method, the sensor has the advantages of compact structure, anti-electromagnetic interference, large measuring range, and good linearity, which can be widely used in the sensing and measurement of extreme high temperature environments such as aero-engine tail injection temperature monitoring, combustion chamber temperature monitoring of aero-engine simulation test benches.

Lagoon coral microbiomes and their potential relationship with adaptation of coral holobionts to extreme high-temperature environments

Numerous corals can survive in high-temperature environments, but little attention has been paid to the microbiome of lagoon corals and their potential adaptation to thermal environments. In this study, we explored this issue by analyzing the coral-symbiotic Symbiodiniaceae, Symbiodiniaceae densities, and bacterial communities among coral species and seawater in the lagoon regions of the southern South China Sea (SCS). Galaxea fascicularis had the highest Symbiodiniaceae density and relative abundance of heat-tolerant Symbiodiniaceae (Durusdinium trenchii), and Acropora cytherea had the lowest density, but the highest diversity, of Symbiodiniaceae. The Symbiodiniaceae diversity of Fungia fungites was the lowest. Moreover, the Symbiodiniaceae community and diversity differed significantly between the lagoon and open-ocean seawater. In addition, the relative abundance of Vibrio was higher in coral holobionts than in the lagoon seawater samples. The relative abundance of Ruegeria was highest in A. cytherea, indicating that coral-associated bacteria in the lagoon were affected by high thermal stress during summer. However, corals in the lagoon may adopt different adaptation strategies for high-temperature environments. G. fascicularis corals may adapt to lagoon environments by symbiosis with heat-tolerant Symbiodiniaceae at high densities and abundance, whereas A. cytherea may survive in the lagoon environment based on a highly flexible symbiosis associated with the high photosynthetic efficiency of Symbiodiniaceae and bacteria.

Ultralight, compressible, and high-temperature-resistant dual-phase SiC/Si3N4 felt for efficient electromagnetic wave attenuation

The ingenious multicomponent microstructure design provides a suitable strategy for gaining high-performance multi-functional integrated materials. Herein, the thermally stable SiC/Si3N4 composite ceramic felt was successfully fabricated via two-step carbothermal reduction processes for advanced electromagnetic (EM) wave absorption properties with strong absorption and a broad effective absorption bandwidth. X-ray absorption near-edge structure (XANES) at the C K-edge and N K-edge of as-prepared samples were investigated to understand the conversion process and electronic structures. The abundant heterogeneous interfaces and complex morphology improved the superior absorption performance by forming excellent impedance matching, multiple interfacial polarization and dipolar polarization generated from the synergistic interaction of SiC and Si3N4 dual-phase felt. The prepared SiC/Si3N4 composite ceramic felt exhibited high absorption efficiency with a minimal reflection loss of –50 dB (exceeding 99.99% wave absorption) and wide absorption band (covering 7 GHz) with a thin thickness of 2.1 mm. Furthermore, the excellent structural robustness and resilient compressibility inherited from C felt, as well as the thermostability until 950 °C under O2 guarantee the stable and durable application of the SiC/Si3N4 composite ceramic felt to resist EM absorbers, especially for in extreme high-temperature environments.

Enhancement of thermal shock resistance in β-Si3N4 coating with in situ synthesized β-Si3N4 nanowires/nanobelts on porous Si3N4 ceramics

A dense β-Si3N4 coating toughened by β-Si3N4 nanowires/nanobelts was prepared by a combined technique involving chemical vapor deposition and reactive melt infiltration to protect porous Si3N4 ceramics in this work. A porous β-Si3N4 nanowires/nanobelts layer was synthesized in situ on porous Si3N4 ceramics by chemical vapor deposition, and then Y–Si–Al–O–N silicate liquid was infiltrated into the porous layer by reactive melt infiltration to form a dense composite coating. The coating consisted of well-dispersion β-Si3N4 nanowires/nanobelts, fine β-Si3N4 particles and small amount of silicate glass. The testing results revealed that as-prepared coating displayed a relatively high fracture toughness, which was up to 7.9 ± 0.05 MPa m1/2, and it is of great significance to improve thermal shock resistance of the coating. After thermal cycling for 15 times at ΔT = 1200 °C, the coated porous Si3N4 ceramics still had a high residual strength ratio of 82.2%, and its water absorption increased only to 6.21% from 3.47%. The results will be a solid foundation for the application of the coating in long-period extreme high temperature environment.

Influence of extreme high-temperature environment and hydration time on the rheology of cement slurry

As a large number of projects are being constructed in deep rock masses, high ground temperatures and hot water disasters are inevitably encountered during construction. Considering the design of grouting parameters and the actual reinforcement effect, it is important to study rheology of grouting materials in high ground temperature environments. This study investigated the influences of temperature and hydration time on the rheology of Portland cement. The water-cement ratio (W/C) of Portland cement PO42.5 varied from 0.5 to 2.0. Through design experiments, the rheological models and parameters (yield stress, plastic viscosity) of cement slurry with different degrees of hydration were studied at different temperatures from 30°C to 80°C. The results show that cement slurries with different water-cement ratios (W/Cs) belong to three flow patterns in different temperature environments. The flow pattern hardly changed during grouting. The rheological model of slurry was controlled by W/C. In addition, the influence of temperature on shear stress varied with the change of W/C. The increase in hydration time increased the shear stress of the slurry for each W/C. The constitutive equation considering the effects of temperature and hydration time was established. This research can provide necessary guidance for the establishment of grouting diffusion theory and numerical model in high ground temperature environment.

Ketamine Stability over Six Months of Exposure to Moderate and High Temperature Environments

Background: All medications should be stored within temperature ranges defined by manufacturers, but logistical and operational challenges of prehospital and military settings complicate adherence to these recommendations. Lorazepam and succinylcholine experience clinically relevant heat-related degradation, whereas midazolam does not. Because ketamine’s stability when stored outside manufacturer recommendations is unknown, we evaluated the heat-related degradation of ketamine exposed to several temperature ranges. Methods: One hundred twenty vials of ketamine (50 mg/mL labeled concentration) from the same manufacturer lot were equally distributed and stored for six months in five environments: an active EMS unit in southwest Ohio (May-October 2019); heat chamber at constant 120 °F (C1); heat chamber fluctuating over 24 hours from 86 °F-120 °F (C2); heat chamber fluctuating over 24 hours from 40 °F-120 °F (C3); heat chamber kept at constant 70 °F (manufacturer recommended room temperature, C4). Four ketamine vials were removed every 30 days from each environment and sent to an FDA-accredited commercial lab for high performance liquid chromatography testing. Data loggers and thermistors allowed temperature recording every minute for all environments. Cumulative heat exposure was quantified by mean kinetic temperature (MKT), which accounts for additional heat-stress over time caused by temperature fluctuations and is a superior measure than simple ambient temperature. MKT was calculated for each environment at the time of ketamine removal. Descriptive statistics were used to describe the concentration changes at each time point. Results: The MKT ranged from 73.6 °F-80.7 °F in the active EMS unit and stayed constant for each chamber (C1 MKT: 120 °F, C2 MKT: 107.3 °F, C3 MKT: 96.5 °F, C4 MKT: 70 °F). No significant absolute ketamine degradation, or trends in degradation, occurred in any environment at any time point. The lowest median concentration occurred in the EMS-stored samples removed after 6 months [48.2 mg/mL (47.75, 48.35)], or 96.4% relative strength to labeled concentration. Conclusion: Ketamine samples exhibited limited degradation after 6 months of exposure to real world and simulated extreme high temperature environments exceeding manufacturer recommendations. Future studies are necessary to evaluate ketamine stability beyond 6 months.

High-temperature stereo-digital image correlation using a single polarization camera.

We propose a new, to the best of our knowledge, full-frame, single-camera stereo-digital image correlation (stereo-DIC) technique that is capable of measuring surface profile and deformation over a wide temperature range. This technique uses a single polarization camera and a polarizing beam splitter to synchronously capture two full-frame sub-images with orthogonal polarization directions. By further adopting the idea of active imaging that combines monochromatic blue-light active lighting and narrow bandpass filter imaging, this system can capture stable and high-contrast speckle images of specimens at extremely high temperatures. From the captured sub-image pairs, profile and deformation fields can be retrieved using a regular stereo-DIC algorithm. Compared with the existing full-frame single-camera stereo-DIC systems implemented on a color camera, the established system offers wider applicability, since it is insensitive to serious variations in ambient light in non-laboratory environments and to the thermal radiation of hot objects in extreme high-temperature environments. The effectiveness and accuracy of the proposed technique are validated by room-temperature tests and high-temperature tests at up to 1000°C. The advantages of a simple configuration, free synchronization, and full-frame high-temperature deformation measurement ability offer the proposed technique potential in both high-speed and high-temperature 3D measurement applications.

Al-rich AlGaN based transistors

Research results for AlGaN-channel transistors are reviewed as they have progressed from low Al-content and long-channel devices to Al-rich and short-channel RF devices. Figure of merit (FOM) analysis shows encouraging comparisons relative to today’s state-of-the-art GaN devices for high Al-content and elevated temperatures. Critical electric field (EC), which fuels the AlGaN transistor FOM for high Al-composition, is not measured directly, but average gate-drain electric field at breakdown is substantially better in multiple reported AlGaN-channel devices compared to GaN. Challenges for AlGaN include the constraints arising from relatively low room temperature mobility dominated by ternary alloy scattering and the difficulty of making low-resistivity Ohmic contacts to high Al-content materials. Nevertheless, considerable progress has been made recently in the formation of low-resistivity Ohmic contacts to Al-rich AlGaN by using reverse compositional grading in the semiconductor, whereby a contact to a lower-Al alloy (or even to GaN) is made. Specific contact resistivity (ρc) approaching ρc ∼ 2 × 10−6 Ω cm2 to AlGaN devices with 70% Al-content in the channel has been reported. Along with scaling of the channel length and tailoring of the threshold voltage, this has enabled a dramatic increase in the current density, which has now reached 0.6 A/mm. Excellent ION/IOFF current ratios have been reported for Schottky-gated structures, in some cases exceeding 109. Encouraging RF performance in Al-rich transistors has been reported as well, with fT and fmax demonstrated in the tens of gigahertz range for devices with less than 150 nm gates. Al-rich transistors have also shown lesser current degradation over temperature than GaN in extreme high-temperature environments up to 500 °C, while maintaining ION/IOFF ratios of ∼106 at 500 °C. Finally, enhancement-mode devices along with initial reliability and radiation results have been reported for Al-rich AlGaN transistors. The Al-rich transistors promise to be a very broad and exciting field with much more progress expected in the coming years as this technology matures.

Anisotropic thermal conductivity under compression in two-dimensional woven ceramic fibers for flexible thermal protection systems

Flexible thermal protection materials made from two-dimensional woven ceramics fibers are of significant interest for hypersonic inflatable aerodynamic decelerators being developed by NASA for future missions on Mars and other planets. A key component of the thermal shield is a heat-resistant outer ceramic fabric that must withstand harsh aero-thermal atmospheric entry conditions. However, a predictive understanding of heat conduction processes in complex woven-fiber ceramic materials under deformation is currently lacking. This article presents a combined experimental and computational study of thermal conductivity in 5-harness-satin woven Nextel 440 fibers, using the hot-disk transient plane source method and computational thermo-mechanical modeling by finite-element analysis. The objective is to quantify and understand the effect of compressive strain on anisotropic heat conduction in flexible two-dimensional ceramic materials. We find, both experimentally and theoretically, that thermal conductivity of woven fabrics rises in both in-plane and out-of-plane directions, as the transverse load increases. Air gap conduction and fiber-to-fiber contacts are shown to play a major role in this behavior. Our finite-element simulations suggest that the thermal conductivity anisotropy is strong because heat transfer of air confined between fibers is reduced compared to that of free air. The proposed modeling methodology accurately captures the experimental heat conduction results and should be applicable to more complex loading conditions and different woven fabric materials, relevant to extreme high temperature environments.

Interface characteristics comparison of sapphire direct and indirect wafer bonded structures by transmission electron microscopy

In this paper, we demonstrate a hydrophilic sapphire wafer bonding method combining plasma-activation and high-temperature bonding process. It is successfully employed in two sapphire bonding structures, including sapphire direct bonding and sapphire indirect bonding based on an intermediate amorphous Al2O3 (a-Al2O3). Transmission electron microscopy (TEM) results show that the a-Al2O3 turns to be the single crystalline phase due to the induction of the sapphire substrate after high temperature bonding at 1000 °C. Moreover, high bonding strength is achieved for sapphire/sapphire (9.91 MPa) and sapphire/Al2O3/sapphire (17.96 MPa) structures and exceeds that of the bulk sapphire. This sapphire bonded structure with cavity can be applied to fabricate optical devices and pressure and temperature sensors for extreme high temperature environments.

Regenerated Fiber Bragg Grating Sensing System for Ultrasonic Detection in a 900 °C Environment

Heat-resistant composites, such as ceramic matrix composites and heat-resistant carbon fiber reinforced plastics (CFRPs), are expected to be used for aircraft engine parts. The development of reliable heat-resistant composite materials requires the use of nondestructive test techniques for evaluating the progression of damage during material testing at elevated temperatures. Furthermore, structural health monitoring (SHM) technologies that operate under harsh environments are expected to be realized for monitoring heat-resistant composite structures. To provide potential solutions for the establishment of such technologies, this research developed a heat-resistant ultrasonic sensor based on a regenerated fiber-optic Bragg grating (RFBG). First, we fabricated an RFBG by annealing a normal fiber-optic Bragg gratings (FBG) sensor. Because the RFBG exhibits high heat resistance at temperatures of 1000 °C, the sensor achieved stable ultrasonic detection at an elevated temperature. In addition, we attempted to use a π-phase-shifted FBG (PSFBG) as the seed grating to construct an ultrasonic sensor with enhanced performance. As a result, the regenerated phase-shifted fiber-optic Bragg grating (R(PS)FBG) sensor possessed a very short effective gauge length and achieved a broad frequency response to ultrasonic waves with frequencies greater than 1.5 MHz. The broadband detectability enables the R(PS)FBG sensor to acquire an accurate response to ultrasonic waves. Hence, we believe the regenerated Bragg grating-based ultrasonic sensors can contribute to establishing an effective nondestructive evaluation method for composite materials, thereby enabling a structural health monitoring system for a composite-made structure operating under extreme high-temperature environments.

Artificial propagation of the endangered Rumanian endemic warm water rudd (Scardinius racovitzai Müller 1958, Cyprinidae, Cypriniformes) for conservation needs

Scardinius racovitzai appeared to be locally adapted to an extreme high temperature environment (26–35 °C). As a species of conservation concern, due to declining ecological condition of the solitary thermal lake it could be found in (Lake Petea, Oradea, Romania) and eventual near complete abstraction of this lake, 60 adults were saved in 2014. In this study we investigated methods for induced spawning and sperm cryopreservation to aid recovery and reintroduction to restored habitats. Induced spawning was introduced successfully by intraperitoneal induction of dried carp pituitary extract and human chorion gonadotropin. Larvae and juveniles were successfully reared to age 3 months using standard methods for cyprinids. Our experiments on the cryopreservation of S. racovitzai sperm show that the extender consisting 40 mM KCl 200 mM glucose, 30 mM Tris buffered with HCL pH 8.0 is suitable for freezing warm water rudd sperm together with methanol as a cryoprotectant. By rescuing the remaining wild stock into captivity and undertaking propagation research we have prevented extinction of this rare species – more so S. racovitzai will be important in the study of freshwater fishes and how they can adapt to significant warming.

First principles study of ceramic materials (IVB group carbides) under ultrafast laser irradiation**Project supported by the National Natural Science Foundation of China (Grant Nos. 11474207 and 11374217).

Group IVB carbides have been applied in extreme aerospace environments as hard ceramic coatings; ZrC is being considered as a replacement for SiC in nuclear reactors. Therefore, a thorough understanding of the laser irradiation response of group IVB carbides is of clear significance. However, the existing knowledge on the fundamental properties of IVB group carbides is limited and insufficient with regard to both irradiated and non-irradiated characteristics. We investigate the effect of ultrafast laser irradiation on the lattice stability of ceramic materials (IVB group carbides) using the density functional perturbation theory (DFPT). The calculated phonon frequencies of TiC and ZrC at the ground state are in good agreement with previous calculations and experimental values. The phonon frequencies of IVB group carbides are positive, even though the electronic temperature reached 5 eV. Thus, IVB group carbides are more stable under ultrafast laser irradiation, which has greater benefits in nuclear and aeronautical applications compared to metals (W, Na), semimetals (Bi), and semiconductors (Si, SiC). The thermodynamic properties of ZrC are calculated as functions of their lattice temperature at different electronic temperatures. The elastic shear constants of IVB group carbides satisfy the Born stability criteria at Te = 5 eV. In addition, a comparison of the predicted melting temperatures of IVB group carbides, reveal that HfC is better suited for extreme high-temperature environments.

Fabrication and Characterization of Additive Manufactured Nickel-Based Oxide Dispersion Strengthened Coating Layer for High-Temperature Application

Increasing turbine inlet temperature is important for improving the efficiency of gas turbine engine. Elevated thermal load causes severe oxidation and corrosion for base alloy in turbine airfoils. To survive in this extreme high-temperature and harsh oxidation environment, both outside protection like thermal barrier coatings (TBC) and inside air cooling have been applied to turbine blades. Significantly more protection can be achieved if the cooling channels are embedded near surface, constructed partially by the coating system and partially by the superalloy substrate. However, neither the ceramic coating layer nor the metallic bond coating layer in current TBC system can provide structural support to such internal cooling channels. Development of structural bond coating layers consequently becomes one of the key technologies to achieve this goal. The present study proposed a method to fabricate structural coating layers on top of turbine blades with the aid of additive manufacturing (AM) and oxide dispersion strengthened (ODS) nickel-based alloy. ODS powder comprised of evenly distributed host composite particles (Ni, Al, Cr) with oxide coating layers (Y2O3) was subjected to a direct metal laser sintering (DMLS) process to fabricate a desirable structural coating layer above nickel-based superalloy substrates. Systematic experimental tests were carried out focusing on the interface adhesion, mechanical strength, microstructure, and surface finish of the ODS coating layer. Based on characterization results from indentation tests and microscopy observations, an optimal coating quality was obtained under ∼250 W laser power. The selected samples were then characterized under isothermal conditions of 1200 °C for 2000 h. Scanning electron microscope (SEM) observations and energy-dispersive X-ray spectroscopy (EDX) analysis were conducted in different stages of the oxidation process. Results indicated a formation of Al2O3 scale on top of the ODS coating layer at early stage, which showed long-term stability throughout the oxidation test. The formation of a stable alumina scale is acting as a protective layer to prevent oxygen penetrating the top surface. Spallation of part of nickel oxide and chromium oxide is observed but the thickness of oxide scale is almost no change. In addition, the observed adhesion between ODS coating layer and substrate was tight and stable throughout the entire oxidation test. The present study has provided strong proof that additive manufacturing has the capability to fabricate structural and protective coating layers for turbine airfoils.

高温で計測可能な光ファイバ超音波センサの構築

Because of the stable material property of optical fiber up to 1000℃, fiber-optic Bragg grating (FBG) sensor is considered as one of possible ultrasonic sensors used at ultrahigh temperature. However, disappearance of reflectivity of a normal FBG in the high temperature above 900℃ makes the ultrasonic detection impossible. In order to detect ultrasonic wave under high temperature environments, we conducted an anneal heat treatment to produce a regenerated fiber Bragg grating (RFBG) sensor. Because the RFBG has a stable reflectivity even at temperature of 1000℃, we detected the ultrasonic wave successfully at the temperature. Especially, because a π-phase-shifted FBG (PSFBG) was used as the seed grating, the RFBG sensor possessed very short effective gauge length that resulted in a broad bandwidth response to ultrasonic wave over 1 MHz. Hence, we believe that the ultrasonic RFBG sensors could be potentially applied for ultrasonic detection in non-destructive tests to evaluate microscopic damage in materials under extreme high-temperature environment.

Single-camera stereo-digital image correlation with a four-mirror adapter: optimized design and validation

A low-cost, easy-to-implement but practical single-camera stereo-digital image correlation (DIC) system using a four-mirror adapter is established for accurate shape and three-dimensional (3D) deformation measurements. The mirrors assisted pseudo-stereo imaging system can convert a single camera into two virtual cameras, which view a specimen from different angles and record the surface images of the test object onto two halves of the camera sensor. To enable deformation measurement in non-laboratory conditions or extreme high temperature environments, an active imaging optical design, combining an actively illuminated monochromatic source with a coupled band-pass optical filter, is compactly integrated to the pseudo-stereo DIC system. The optical design, basic principles and implementation procedures of the established system for 3D profile and deformation measurements are described in detail. The effectiveness and accuracy of the established system are verified by measuring the profile of a regular cylinder surface and displacements of a translated planar plate. As an application example, the established system is used to determine the tensile strains and Poisson׳s ratio of a composite solid propellant specimen during stress relaxation test. Since the established single-camera stereo-DIC system only needs a single camera and presents strong robustness against variations in ambient light or the thermal radiation of a hot object, it demonstrates great potential in determining transient deformation in non-laboratory or high-temperature environments with the aid of a single high-speed camera.

Optimization of a three-dimensional digital image correlation system for deformation measurements in extreme environments

An optimized 3D digital image correlation (3D-DIC) system using active optical imaging is developed for accurate shape and 3D deformation measurements in nonlaboratory conditions or extreme high-temperature environments. In contrast to a conventional 3D-DIC system using white or natural light illumination, the proposed active imaging 3D-DIC system is based on a combination of monochromatic lighting and bandpass filter imaging. Because the bandpass filter attached before the imaging lenses allows only the actively illuminated monochromatic light to pass through and blocks all light outside of its bandpass range, the active imaging 3D-DIC system is therefore insensitive to serious variations in ambient light in nonlaboratory environments and to the thermal radiation of hot objects in extreme high-temperature environments. Two challenging experiments that cannot be performed by a conventional 3D-DIC system were carried out to verify the robustness and accuracy of the developed active imaging 3D-DIC system. Because a much wider application range can be achieved with relatively simple and easy-to-implement improvements, the proposed active imaging 3D-DIC system is highly recommended for practical use instead of the conventional 3D-DIC system.