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At least 883 records · Page 49
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

An Experimental Study on Low Pressure Frost Formation for Lunar Polar Water Capture

In-situ resource utilization (ISRU) is a vital component of NASA’s mission to the Moon and beyond, as the extraction of resources from the environment can reduce payload weight and the frequency of resupply missions. Since the discovery of water in the regolith of the permanently shadowed regions (PSR) of the Moon, its extraction and transport has become an area of increasing interest for NASA. One proposed method is heating icy regolith to free the water before desublimating and transporting it as ice in a tanker. However, little is known regarding the dynamics of frost growth at low pressures, and an understanding of the heat transfer process is required to properly size the heat exchanger for the tanker. To investigate this phenomenon, a cold plate was placed in a vacuum chamber with water vapor directed at its surface. The chamber pressure (300 and 500 Pa) and cold plate temperature (–18 to –5 °C) were kept below the triple point and varied throughout the experiment to examine their impact on frost layer heat transfer. As water flowed into the chamber and deposited on the cold plate surface, the heat flux and temperature were measured along with the frost layer thickness and/or mass. Density calculated at the conclusion of each test suggests the frost layer is denser than that of frost grown at atmospheric pressure. The results demonstrate unexpected density and heat transfer characteristics and require development of a new model of frost growth for lunar conditions.

In situ Resource Utiliztion↗
NASA NTRSDate not supplied

An Experimental Study on Low Pressure Frost Formation for Lunar Polar Water Capture

In-situ resource utilization (ISRU) is a vital component of NASA’s mission to the Moon and beyond, as the extraction of resources from the environment can reduce payload weight and the frequency of resupply missions. Since the discovery of water in the regolith of the permanently shadowed regions (PSR) of the Moon, its extraction and transport has become an area of increasing interest for NASA. One proposed method is heating icy regolith to free the water before de-sublimating and transporting it as ice in a tanker. However, little is known regarding the dynamics of frost growth at low pressures, and an understanding of the heat transfer process is required to properly size the heat exchanger for the tanker. To investigate this phenomenon, a cold plate was placed in a vacuum chamber with water vapor directed at its surface. The chamber pressure (300 and 500 Pa) and cold plate temperature (–18 to –5 °C) were kept below the triple point and varied throughout the experiment to examine their impact on frost layer heat transfer. As water flowed into the chamber and deposited on the cold plate surface, the heat flux and temperature were measured along with the frost layer thickness and/or mass. Density calculated at the conclusion of each test suggests the frost layer is denser than that of frost grown at atmospheric pressure. The results demonstrate unexpected density and heat transfer characteristics and require development of a new model of frost growth for lunar conditions

Lunar polar↗
NASA NTRS2014

Visualization of Capsule Reentry Vehicle Heat Shield Ablation Using Naphthalene PLIF

The Orion Multi-Purpose Crew Vehicle (MPCV) will use an ablative heat shield and improved understanding of the ablation process would be beneficial for design purposes. Given that ablation is a multi-physics process involving heat and mass transfer, codes aiming to predict heat shield ablation are in need of experimental data pertaining to the turbulent transport of ablation products for validation. At The University of Texas at Austin, a technique is being developed that uses planar laser-induced fluorescence (PLIF) of a low-temperature sublimating ablator (naphthalene) to visualize the transport of ablation products in a supersonic flow. Since ablation at reentry temperatures can be difficult to recreate in a laboratory setting it is desirable to create a limited physics problem and simulate the ablation process at relatively low temperature conditions using naphthalene. A scaled Orion MPCV model with a solid naphthalene heat shield has been tested in a Mach 5 wind tunnel at various angles of attack in the current work. PLIF imaging reveals the distribution of the ablation products as they are transported into the heat-shield boundary layer and over the capsule shoulders into the separated shear layer and backshell recirculation region. Visualizations of the capsule shear layer using both naphthalene PLIF and Schlieren imaging compared favorably. High concentrations of naphthalene in the capsule separated flow region, intermittent turbulent structures on the heat shield surface, and interesting details of the capsule shear layer structure were observed using the naphthalene PLIF technique. The capsule shear layer was also shown to generally appear to be more turbulent at lower angles of attack. Furthermore, the PLIF signal increased steadily over the course of a run indicating that during a wind tunnel run the model heated up and the rate of naphthalene ablation increased. The shear layer showed increasing signs of turbulence over the course of a wind tunnel run as well, likely because of the combination of increased surface roughness and surface blowing rate. PLIF imaging also detected regions with a relatively low concentration of naphthalene in the capsule backshell recirculation region that are most likely the result of cross-flow-induced vortices on the capsule afterbody.

Combs, Christopher S.↗
DOE OSTI2015

Waste Heat to Power Market Assessment

Waste heat to power (WHP) is the process of capturing heat discarded by an existing process and using that heat to generate electricity. In the industrial sector, waste heat streams are generated by kilns, furnaces, ovens, turbines, engines, and other equipment. In addition to processes at industrial plants, waste heat streams suitable for WHP are generated at field locations, including landfills, compressor stations, and mining sites. Waste heat streams are also produced in the residential and commercial sectors, but compared to industrial sites these waste heat streams typically have lower temperatures and much lower volumetric flow rates. The economic feasibility for WHP declines as the temperature and flow rate decline, and most WHP technologies are therefore applied in industrial markets where waste heat stream characteristics are more favorable. This report provides an assessment of the potential market for WHP in the industrial sector in the United States.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2014

Effect of the fissile bead's and thermocouple wires’ sizes on the response time of a fission couple

The fission couple is proposed as a fast response miniature neutron detector in the measurement of time dependent energy depositions within the fissile material based on theoretical analysis, but the response time of a fission couple is relatively slow in practice. The time lag originated from heat transfer process was demonstrated to be the dominating factor by theoretical simulations and experimental verification in this paper. The response of a fission couple as a function of the bead size and the thermocouple wires’ sizes are simulated using ANSYS workbench. The decrease of wires’ diameter results in the decrease of response time, and the increase of bead's diameter leads to a slight increase of response time. During a pulse heating transient in the fuel of Chinese Fast Burst Reactor II with a FWHM of 181μs, the time lag originated from heat transfer process is about tens of microseconds for the peaks of the change rate of temperature, and is of the order of milliseconds to achieve 85% of the temperature rise for a typical fission couple with a Φ 1 mm fissile bead and two Φ 0.05 mm thermocouple wires. The results obtained provide foundation for the optimization of fission couples.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2024

Investigations of atomic and molecular processes of NBI-heated discharges in the MAST Upgrade Super-X divertor with implications for reactors

This experimental study presents an in-depth investigation of the performance of the MAST-U Super-X divertor during NBI-heated operation (up to 2.5 MW) focussing on volumetric ion sources and sinks as well as power losses during detachment. The particle balance and power loss analysis revealed the crucial role of Molecular Activated Recombination and Dissociation (MAR and MAD) ion sinks in divertor particle and power balance, which remain pronounced in the change from ohmic to higher power (NBI heated) L-mode conditions. The importance of MAR and MAD remains with double the absorbed NBI heating. MAD results in significant power dissipation (up to ${\sim} 20\%$ of $P_\textrm{SOL}$), mostly in the cold ($T_e \lt 5$ eV) detached region. Theoretical and experimental evidence is found for the potential contribution of $D^-$ to MAR and MAD, which warrants further study. These results suggest that MAR and MAD can be relevant in higher power conditions than the ohmic conditions studied previously. Post-processing reactor-scale simulations suggests that MAR and MAD can play a significant role in divertor physics and synthetic diagnostic signals of reactor-scale devices, which are currently underestimated in exhaust simulations. This raises implications for the accuracy of reactor-scale divertor simulations of particularly tightly baffled (alternative) divertor configurations.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
NASA NTRS2008

Thermal Capacitance (Slug) Calorimeter Theory Including Heat Losses and Other Decaying Processes

A mathematical model, termed the Slug Loss Model, has been developed for describing thermal capacitance (slug) calorimeter behavior when heat losses and other decaying processes are not negligible. This model results in the temperature time slope taking the mathematical form of exponential decay. When data is found to fit well to this model, it allows a heat flux value to be calculated that corrects for the losses and may be a better estimate of the cold wall fully catalytic heat flux, as is desired in arc jet testing. The model was applied to the data from a copper slug calorimeter inserted during a particularly severe high heating rate arc jet run to illustrate its use. The Slug Loss Model gave a cold wall heat flux 15% higher than the value of 2,250 W/sq cm obtained from the conventional approach to processing the data (where no correction is made for losses). For comparison, a Finite Element Analysis (FEA) model was created and applied to the same data, where conduction heat losses from the slug were simulated. The heat flux determined by the FEA model was found to be in close agreement with the heat flux determined by the Slug Loss Model.

Hightower, T. Mark↗
DOE OSTI2016

Development of joining technology using local heating for SiC fuel cladding

Silicon carbide (SiC) is an attractive material for an accident-tolerant fuel in light water reactors because of its lower hydrogen-generation rate and lower heat of reaction than conventional Zircaloy. On the other hand, practical application of SiC fuel cladding faces a lot of critical issues, one of which is end-plug joining. The objective of this study is to clarify the feasibility of end-plug joining by silicon brazing using local heating by evaluating the shear strength of joint specimens and producing a circumferential joint experimentally. Silicon is thought to be a compatible joining material with SiC because as well as being a constituent of SiC, its thermal-expansion coefficient is close to that of SiC. Local heating using processes such as laser irradiation and a resistance-heating element needs to be applied for end-plug joining. Brazing is expected to seal a cladding with an end plug by using brief heating without a strong compression force. Shear strength was evaluated using specimens with silicon-brazing joints processed using laser irradiation. The joint sections without defects showed shear strengths higher than or equal to 59 MPa at temperatures from normal room temperature to 1473 K. The average shear strength of the joint (99 MPa) is comparable to that of a diffusion-bonding joint using titanium or molybdenum foil. A tube and a plug were circumferentially joined with silicon brazing using laser irradiation or a graphite heating element. A defocused laser beam was effective for joining without cracking during laser irradiation. Although local heating using a resistance-heating element can more easily control the temperature of the joint, it took longer processing time than that using laser irradiation due to limited temperature-increase rate in order to avoid thermal shock damage. (authors)

36 MATERIALS SCIENCE↗
NASA NTRS1991

In-space experiment on thermoacoustic convection heat transfer phenomenon-experiment definition

The definition phase of an in-space experiment in thermoacoustic convection (TAC) heat transfer phenomenon is completed and the results are presented and discussed in some detail. Background information, application and potential importance of TAC in heat transfer processes are discussed with particular focus on application in cryogenic fluid handling and storage in microgravity space environment. Also included are the discussion on TAC space experiment objectives, results of ground support experiments, hardware information, and technical specifications and drawings. The future plans and a schedule for the development of experiment hardware (Phase 1) and flight tests and post-flight analysis (Phase 3/4) are also presented. The specific experimental objectives are rapid heating of a compressible fluid and the measurement of the fluid temperature and pressure and the recording and analysis of the experimental data for the establishment of the importance of TAC heat transfer process. The ground experiments that were completed in support of the experiment definition included fluid temperature measurement by a modified shadowgraph method, surface temperature measurements by thermocouples, and fluid pressure measurements by strain-gage pressure transducers. These experiments verified the feasibility of the TAC in-space experiment, established the relevance and accuracy of the experimental results, and specified the nature of the analysis which will be carried out in the post-flight phase of the report.

Parang, M.↗
DOE OSTI2019

Cutting edge research and new technologies in heat and mass transfer processes of refrigeration and air conditioning systems

This special edition of the Science and Technology for the Built Environment (STBE) presents eight selected articles originally presented at the 17th International Refrigeration and Air Conditioning Conference held at Purdue University, West Lafayette, IN, USA, during July 9–12, 2018. All eight articles were significantly expanded with additional technical content and received full peer review before being finally accepted for publication in this special issue of the STBE. The eight articles in this special issue cover a wide range of topics from condensation and evaporation of low global warming potential (LGWP) refrigerants to phase change material storage for personal cooling systems, from frosting on hydrophilic and hydrophobic coated surfaces to geometry optimization of heat exchanger fins. Furthermore, these articles describe cutting-edge research and feasibility studies of new technologies that were recently investigated for refrigeration and air conditioning applications.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2018

A Review of Metastable Beta Titanium Alloys

In this article, we provide a broad and extensive review of beta titanium alloys. Beta titanium alloys are an important class of alloys that have found use in demanding applications such as aircraft structures and engines, and orthopedic and orthodontic implants. Their high strength, good corrosion resistance, excellent biocompatibility, and ease of fabrication provide significant advantages compared to other high performance alloys. The body-centered cubic (bcc) ß-phase is metastable at temperatures below the beta transus temperature, providing these alloys with a wide range of microstructures and mechanical properties through processing and heat treatment. One attribute important for biomedical applications is the ability to adjust the modulus of elasticity through alloying and altering phase volume fractions. Furthermore, since these alloys are metastable, they experience stress-induced transformations in response to deformation. The attributes of these alloys make them the subject of many recent studies. In addition, researchers are pursuing development of new metastable and near-beta Ti alloys for advanced applications. In this article, we review several important topics of these alloys including phase stability, development history, thermo-mechanical processing and heat treatment, and stress-induced transformations. In addition, we address recent developments in new alloys, phase stability, superelasticity, and additive manufacturing.

beta phase, metastable, titanium, aircraft, biomed↗
DOE OSTI2023

Fuel Injection Dynamics and Composition Effects on RDE Performance

Rotating detonation engines (RDEs) provide a promising route to substantially increasing cycle efficiency in stationary gas turbines. Much of this increase relies on the ability to achieve consistent pressure gain within the combustor. In particular, the design of injectors that feed fuel and air into the detonation channel plays a crucial role. Such injectors have to ensure proper mixing of fuel and oxidizer, while minimizing backflow of detonation products into the feed plenums, and reduce susceptibility to the complex wave structures that exist within the combustor. From a practical perspective, such RDEs also need to operate with variable fuel composition. When fuel mixtures with components that possess vastly different oxidation pathways and time-scales are used, there could be additional losses through deflagrative burning instead of detonation-driven heat release. Such sensitivity to the complete flow path is akin to the physics of thermoacoustic instabilities in conventional gas turbines. In this sense, RDEs pose a unique research challenge: the performance of the device relies on the small-scale heat release process, which is highly dependent on the flow interactions within the full-scale system. As a result, canonical flow configurations, instrumented with detailed diagnostics or modeled using high-fidelity tools, but only focus on the small-scale processes will not contain the key system-level interactions. At the same time, macroscopic measurements and models that only capture system-level performance will not provide insight into the key sources of pressure losses. These couplings and sensitivities provide a formidable challenge to both experimental and simulation studies of the effects Thus, a joint experimental/computational program designed specifically to address these challenges was undertaken in this program. The focus of this program was on two key topics: a) the interaction between injector flow and the overall wave dynamics within the combustor, and b) the deflagration/detonation structure in multi-component fuels that are of practical interest. Both topics involve interaction of small-scale heat release processes with the geometry-dependent wave structure. Studies focused on the study of full-scale RDE systems, based on a 6-inch conventional annular geometry. Experimentally RDEs were studied using a combination of diagnostics. A combination of optical diagnostics and aero-thermo-acoustic analysis based on a combination of spectral and mode decomposition analysis was used to identify the dynamics of the detonation wave and other secondary waves that exist in the system. These studies have helped the identification and investigation of injector and detonation dynamics arising from coupling, and how they affect RDE mixing, detonation structure, operability and performance. Performance of RDEs was investigated through thrust stand measurements, which was used to evaluate the effective pressure gain generated by the system through the concept of equivalent available pressure. Optical diagnostics were developed and implemented to investigate the distribution of heat release, across the detonation wave. Novel optical diagnostics of NIR imaging was also developed and applied to investigate the high temperature / high pressure distribution across the detonation wave. In order to complement the experiments, the computational tools were geared to simulate the full experimental setup. GPU-based acceleration of the models and computations were developed to enable rapid simulation of the full system. In addition, the use of adaptive mesh refinement, and unstructured grid formulation, enabled the investigation of realistic geometries studied in the laboratory. The simulations produced a wealth of detail on the structure of the detonation wave under different operating conditions. Emphasis was placed on quantifying mixture pre-burning and the impact on wave propagation and structure.

03 NATURAL GAS↗
NASA NTRS1994

The r-process and neutrino-heated supernova ejecta

As a neutron star is formed by the collapse of the iron core of a massive star, its Kelvin-Helmholtz evolution is characterized by the release of gravitational binding energy as neutrinos. The interaction of these neutrinos with heated material above the neutron star generates a hot bubble in an atmosphere that is nearly in hydrostatic equilibrium and heated, after approximately 10 s, to an entropy of S/N(sub AS)k greater than or approximately = 400. The neutron-to-proton ratio for material moving outward through this bubble is set by the balance between neutrino and antineutrino capture on nucleons. Because the electron antineutrino spectrum at this time is hotter than the electron neutrino spectrum, the bubble is neutron-rich (0.38 less than or approximately = Y(sub e) less than or approximately = 0.47). Previous work using a schematic model has shown that these conditions are well suited to the production of heavy elements by the r-process. In this paper we have advanced the numerical modeling of a 20 solar mass 'delayed' supernova explosion to the point that we can follow the detailed evolution of material moving through the bubble at the late times appropiate to r-process nucleosynthesis. The supernova model predicts a final kinetic energy for the ejecta of 1.5 x 10(exp 51) ergs and leaves behind a remnant with a baryon mass of 1.50 solar mass (and a gravitational mass of 1.445 solar mass). We follow the thermodynamic and compositional evolution of 40 trajectories in rho(t), T(t), Y(sub e)(t) for a logarithmic grid of mass elements for the last approximately = 0.03 solar mass to be ejected by the proto-neutron star down to the last less than 10(exp -6) solar mass of material expelled at up to approximately = 18 s after core collapse. We find that an excellent fit to the solar r-process abundance distribution is obtained with no adjustable parameters in the nucleosynthesis calculations. Moreover, the abundances are produced in the quantities required to account for the present Galactic abundances. However, at earlier times, this one-dimensional model ejects too much material with entropies S/N(sub A)k approximately 50 and Y(sub e) approximately 0.46. This leads to an acceptable over production of N = 50 nuclei, particularly Sr-88, Y-89, and Zr-90, relative to their solar abundances. We speculate on various means to avoid the early overproduction and/or ejection of N = 50 isotonic nuclei while still producing and ejecting the correct amount of r-process material.

Woosley, S. E.↗
DOE OSTI2013

Controlling morphology and crystallite size of Cu(In{sub 0.7}Ga{sub 0.3})Se{sub 2} nano-crystals synthesized using a heating-up method

CuIn{sub 0.7}Ga{sub 0.3}Se{sub 2}(CIGS) nano-crystals were successfully synthesized via a heating-up process. The non-coordinating solvent (1-octadecene) and selenium/cations ratio effects on the crystalline phase and crystallite size of CIGS nano-crystallites were investigated. It was observed that the CIGS nano-crystallite morphology changed from sheet into spherical shape as the amount of 1-octadecene addition was increased. CIGS nano-crystals were obtained in 9–20 nm sizes as the selenium/cations ratio increased. These results suggest that the monomer reactivity in the solution can be adjusted by changing the solvent type and selenium/cations ratio, hence affecting the crystallite size and distribution. - Graphical abstract: CuIn{sub 0.7}Ga{sub 0.3}Se{sub 2}(CIGS) nano-crystals were successfully synthesized via a heating-up process in this study. The super-saturation in the solution can be adjusted by changing the OLA/ODE ratio and selenium/cation ratio.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Novel Binderjet Additive Heat Exchangers: A Pathway to 5¢/kWh CSP

General Electric (GE) Research is developing a Binderjet manufacturing processes and heat exchanger core design to enable low-cost high temperature Recuperators (HTR) for Concentrated Solar Power (CSP) supercritical carbon dioxide (sCO2) power cycles. The objective is to show a path for greater than or equal to 10% cost reduction for an HTR that enables meeting the DOE SunShot goal of 5c/kWh for CSP plants. As part of the DOE program, GE is developing a novel trifurcating heat exchanger (HX) for HTR using binderjet additive manufacturing process that could meet the cost targets. As part of the 2021 CSP summit presentation, GE demonstrates that the build control of HX cores using the binderjet process are within the program targets. Preliminary cost estimates of the overall heat exchanger using a modular HX design shows cost reductions greater than 10% target allowing significant margin for assembly and inspections costs. Additional cost reduction plans are also highlighted.

14 SOLAR ENERGY↗
DOE OSTI2012

Y{sub 2}O{sub 3}:Yb/Er nanotubes: Layer-by-layer assembly on carbon-nanotube templates and their upconversion luminescence properties

Graphical abstract: Well-shaped Y{sub 2}O{sub 3}:Yb/Er nanotubes have been successfully synthesized on a large scale via layer-by-layer assembly on carbon nanotubes templates followed by a subsequent heat treatment process. The as-prepared Y{sub 2}O{sub 3}:Yb/Er nanotubes show a strong red emission corresponding to the {sup 4}F{sub 9/2}–{sup 4}I{sub 15/2} transition of the Er{sup 3+} ions under excitation at 980 nm. Display Omitted Highlights: ► Well-shaped Y{sub 2}O{sub 3}:Yb/Er nanotubes have been successfully synthesized. ► CNTs were used as templates for Y{sub 2}O{sub 3}:Yb/Er nanotubes. ► LBL assembly and calcination were used for preparation of Y{sub 2}O{sub 3}:Yb/Er nanotubes. ► The as-prepared Y{sub 2}O{sub 3}:Yb/Er nanotubes show a strong red emission. -- Abstract: Well-shaped Y{sub 2}O{sub 3}:Yb/Er nanotubes have been successfully synthesized on a large scale via layer-by-layer (LBL) assembly on carbon nanotubes (CNTs) templates followed by a subsequent heat treatment process. The crystal structure, element analysis, morphology and upconversion luminescence properties were characterized. XRD results demonstrate that the diffraction peaks of the samples calcinated at 800 °C or above can be indexed to the pure cubic phase of Y{sub 2}O{sub 3}. SEM images indicate that a large quantity of uniform and rough nanotubes with diameters of about 30–60 nm can be observed. The as-prepared Y{sub 2}O{sub 3}:Yb/Er nanotubes show a strong red emission corresponding to the {sup 4}F{sub 9/2}–{sup 4}I{sub 15/2} transition of the Er{sup 3+} ions under excitation at 980 nm, which have potential applications in such fields as nanoscale devices, molecular catalysts, nanobiotechnology, photonics and optoelectronics.

36 MATERIALS SCIENCE↗
NASA NTRS2001

Thermal Processing Effects on the Adhesive Strength of PS304 High Temperature Solid Lubricant Coatings

In this paper the effects of post deposition heat treatments on the cohesive and adhesive strength properties of PS304, a plasma sprayed nickel-chrome based, high temperature solid lubricant coating deposited on stainless steel, are studied. Plasma spray deposited coating samples were exposed in air at temperatures from 432 to 650 C for up to 500 hr to promote residual stress relief, enhance particle to particle bonding and increase coating to substrate bond strength. Coating pull-off strength was measured using a commercial adhesion tester that utilizes 13 mm diameter aluminum pull studs attached to the coating surface with epoxy. Pull off force was automatically recorded and converted to coating pull off strength. As deposited coating samples were also tested as a baseline. The as-deposited (untreated) samples either delaminated at the coating-substrate interface or failed internally (cohesive failure) at about 17 MPa. Samples heat treated at temperatures above 540 C for 100 hr or at 600 C or above for more than 24 hr exhibited strengths above 31 MPa, nearly a two fold increase. Coating failure occurred inside the body of the coating (cohesive failure) for nearly all of the heat-treated samples and only occasionally at the coating substrate interface (adhesive failure). Metallographic analyses of heat-treated coatings indicate that the Nickel-Chromium binder in the PS304 appears to have segregated into two phases, a high nickel matrix phase and a high chromium precipitated phase. Analysis of the precipitates indicates the presence of silicon, a constituent of a flow enhancing additive in the commercial NiCr powder. The exact nature and structure of the precipitate phase is not known. This microstructural change is believed to be partially responsible for the coating strength increase. Diffusion bonding between particles may also be playing a role. Increasing the heat treatment temperature, exposure time or both accelerate the heat treatment process. Preliminary measurements indicate that the heat treatment also results in a one time, permanent coating thickness increase of about 3%. Based upon these results, the incorporation of a heat treatment prior to final finishing has been incorporated in the application process of this coating technology.

DellaCorte, Christopher↗