bluuebunny/crossref_metadata_2025_split huggingface dataset:
Low Pressure Carburizing Distortion Data Comparing Oil and High Pressure Gas Quenching
Authors: Lelong Vincent , Beauchesne Dennis 
Published: March 2024

Abstract
This presentation will discuss data on parts tested in Low Pressure Carburizing using oil and gas quenching. We will present data on metallurgy, distortion and load design to optimize each quenching media. As we know oil and gas quench respond differently, we will explore the evolution of high pressure gas quenching as it exist in today’s market. Low Pressure Carburizing has been growing among OEM’s and now Tier 2 suppliers as well as heat treaters in the Automotive and Aerospace markets. These details should help show the audience that they also can take advantage of the clean environment from Low Pressure Carburizing and just in time processing along with possible distortion control for all their parts currently being atmosphere carburized.
Multiple Chamber Vacuum Furnaces vs. Single-Chamber Vacuum Furnaces—A Review
Authors: Bernard Benjamin T. , Bernard William J. 
Published: March 2024

Abstract
A review of vacuum processing in a multiple-chamber vs. single-chamber vacuum furnace and the advantages and disadvantages of both design concepts will be presented. Cycle calculations will be shown to illustrate the differences in the floor-to-floor time, heating energy required to process and cooling power to quench a normalized load. Additionally, the presentation will discuss the differences in residual atmosphere for a given vacuum level for the two furnace concepts. Differences in operation and maintenance between the two concepts and appropriate processes to run in each will also be discussed.
Optimizing Cycle Time and Process Flexibility Using Vacuum Sealed Quenching
Authors: Marteeny Don , Korecki Maciej 
Published: March 2024

Abstract
Hardening and case hardening are among the most common types of heat treatment processes, which can be performed in either atmosphere or vacuum furnaces. These processes, followed by oil quenching, are carried out in batch sealed quench and continuous furnaces such as pusher, roller, or rotary hearth types. Atmosphere heat treatment technology and equipment was developed more than 60 years ago with little new product innovation or change since. However, in this time period the needs of manufacturing have changed dramatically, driven by global competitiveness and the drive for lower unit cost. As such the heat treatment solutions must be capable of achieving higher productivity (through shorter cycle times), increased flexibility (with respect to material and process/cycles) and meet higher product quality standards. In addition, today’s manufacturing requires absolute process reproducibility and integration with other manufacturing processes, all done using energy efficient and environmentally friendly equipment. The solution to this situation is modern vacuum furnace technology and vacuum equipment that easily adapts to stringent specifications and changing industry standards. In this discussion, two case studies of this technology are presented. The first includes a two-chamber sealed oil quench vacuum furnace to case harden a SAE 5120 component to a surface hardness of 61 HRC using a Low - Pressure Carburizing (LPC) process. The result was a 30% savings over traditional atmosphere carburizing integral quench furnace owned by a commercial heat treater. The second study involves the use of a three-chamber sealed oil quench vacuum furnace to case harden SAE 5115 steel automotive steering components to an effective case depth of 0.9 mm minimum and a minimum surface hardness of 60 HRC. Using LPC these parameters were easily achievable. By, using a three-chamber sealed oil quench furnace, the potential for up to 600 kg/hr throughput was demonstrated, while maintaining costs comparable to a traditional atmosphere style integral quench furnace. Together, both studies show that sealed oil quench vacuum furnaces can improve process time and quality over a traditional atmosphere integral quench furnace while maintaining the process costs needed to remain competitive.
Comparative Investigation of Standard WC-Co and a New WC-FeCrAl Feedstock Powder
Authors: Hussong B. , Pfeiffer J. , Lehmert B. , Wojarski L. , Tillmann W. 
Published: March 2024

Abstract
This study investigates the HVOF spraying characteristics of a new WC-FeCrAl powder as compared to a standard WC-Co feedstock. Significantly higher particle temperatures were recorded for the WC-FeCrAl powder during spraying, presumably an effect of phase reactions during particle dwell time in the jet. XRD graphs revealed W2C and δ-Fe2O3 formations. Gibbs free energy calculations propose that energy is being released during the formation of these phases. Comparable correlations between in-flight particle measurements and splat morphologies were found for both powders. Coating hardness was also found to be comparable, although porosity was significantly lower in the WC-FeCrAl samples. This is attributed to the smaller carbide grain size of the new powder, which might help explain the lower viscosity of the molten particles at impact. A response surface analysis of XRD measurements indicates that W2C formation occurs in the spray jet, and it is assumed that δ-Fe2O3 formation occurs on the surface of the substrate after particle deposition.
Deposition and Oxidation of Oxide-Dispersed CoNiCrAlY Bondcoats
Authors: Okada M. , Vaßen R. , Karger M. , Sebold D. , Mack D.E. , Jarligo M.O. , Bozza F. 
Published: March 2024

Abstract
This study compares the deposition and oxidation behavior of two oxide-dispersed CoNiCrAlY powders, one commercially obtained, the other prepared in a high-energy attrition ball mill using CoNiCrAlY and nanosize α-alumina powders. The custom powder was deposited by HVOF spraying using two sets of parameters, one optimized for CoNiCrAlY powder, the other for fine alumina. Coatings produced under the latter conditions were found to be porous, which can be attributed to a low degree of melting in the dispersed alumina. Isothermal oxidation testing at 1373 K for up to 1000 h in air caused oxidation not only at the surface, but also inside the coatings due to the movement of oxygen through the pores. The coatings deposited under the other set of parameters, i.e., at higher power levels, were free of pores. Isothermal oxidation tests were also carried out on coatings produced from the commercial powder, in this case, by HVOF and as well as vacuum plasma spraying. The coatings obtained by HVOF spraying were found to have a thinner thermally grown oxide layer than not only the VPS coatings, but also conventional metallic bond coats. Internal oxidation in the HVOF coatings is due to insufficient cohesion of the spray particles. Furnace cycling tests were conducted on specimens with an additional ceramic thermal barrier coating. Specimens with VPS bond coats produced from commercial oxide-dispersed powder achieved almost same number of cycles to delamination as specimens with conventional metal bond coats.
Mechanical Properties of Plasma Sprayed YSZ Coatings Measured Using TAT and TCT Test
Authors: Ming Ang Andrew Siao , Berndt Christopher C. 
Published: March 2024

Abstract
This investigation employs tensile adhesion tests (TAT) and tubular coating tensile (TCT) tests to measure the adhesion and cohesion bond strength of plasma sprayed YSZ coatings. Tensile adhesion testing measures the bond strength of the YSZ-bond coat system perpendicular to the spray direction, while tubular coating tensile testing measures the intersplat strength of the YSZ coating parallel to the spray direction. In both cases, the failure strength of the coatings can be approximated to a Weibull distribution, indicative of anisotropic behavior as verified by Knoop microhardness indentation tests. The average coating strength parallel to the spray direction is shown to be about 1.5 times greater than the bond strength perpendicular to the spraying direction.
Y2O3 and Yb2O3 Co-Doped Strontium Hafnate as a New Thermal Barrier Coating Material
Authors: Ma W. , Li P. , Dong H.-Y. , Bai Y. , Zhao J.-L. , Fan X.-Z. 
Published: March 2024

Abstract
This study investigates the phase stability and thermophysical properties of Y2O3 and Yb2O3 co-doped SrHfO3 (SHYY) powder and bulk material along with the phase stability and microstructure evolution of as-sprayed SHYY coatings during annealing. The powder was synthesized by a solid-state reaction at 1450 °C, showing good phase stability up to 1400 °C. Dilatometry measurements revealed no abnormal changes in the coefficient of thermal expansion over a temperature range of 200-1300 °C. The thermal conductivity of the bulk material was found to be 16% lower than that of SrHfO3. Free-standing SHYY coatings deposited by air plasma spraying were also tested. The coatings consisted of SHYY and a minor amount of secondary phase Yb2O3 and exhibited good phase stability during heat treatment at 1400 °C for 288 h. Coating samples examined after 216 h still exhibited a columnar microstructure.
A Novel Modification for Twin Wire Arc Spraying to Improve the Variety of Application
Authors: Tillmann W. , Abdulgader M. , Hagen L. 
Published: March 2024

Abstract
Various approaches are presented in this paper to adapt conventional twin wire arc spraying (TWAS) for the production of smooth and finely structured coatings. Higher particle velocities were achieved by modifying spraying nozzle geometry. New geometries that incorporate a Laval shape produced the highest particle velocities while also eliminating overspray and extending the high-velocity region. This led to a more focused spraying plume and a change in optimal spraying distance, which was found to be more than 200 mm based on coating roughness. Some of the new nozzles exhibited evidence of particle deposition on the inner walls, which can restrict plume flow if not addressed. The problem is related to the position of the Laval throat in the spray plume as well as changes in gas pressure.
High-Temperature Oxidation-Resistant Thermal Spray Coatings Based on MoSi2 for Furnace Applications
Authors: Schuberth S. , Uhlig T. , Pokhmurska H. , Rupprecht C. , Lampke T. 
Published: March 2024

Abstract
The aim of this work is to optimize molybdenum disilicide coatings for high-temperature oxidation protection of metallic surfaces. Agglomerated and sintered MoSi2 powder was deposited on test substrates by atmospheric plasma spraying. The powders and coatings were characterized by means of optical and scanning electron microscopy. Various tests were carried out to determine the influence of powder size and spray parameters on coating porosity, hardness, and adhesive pull strength.
Effect of WC-Co-Cr Powder Properties on Coating Characteristics by Recent HVAF Spraying
Authors: Sato Kazuto , Miyajima Hidenori , Kato Masami , Kitamura Junya , Sakaki Kazuhiko 
Published: March 2024

Abstract
This study investigates the density, hardness, and wear behavior of WC-Co-Cr coatings produced by high-velocity air fuel (HVAF) spraying. The results indicate that coating hardness, density, and wear performance are improved by increasing gas velocity and using powders composed of fine CoCr particles.
Investigation of HVOF-Sprayed Hardmetal Coatings for Static Friction Applications
Authors: Berger L.-M. , Spatzier J. , Gräfensteiner M. , Vidner J. , Leidich E. , Schiefer S. , Gröger S. , Gerlach M. 
Published: March 2024

Abstract
This study investigates the static friction properties of HVOF-sprayed Cr3C2-NiCr coatings. Measurements of the static coefficient of friction (CoF) of as-sprayed coatings show their potential for use in frictionally engaged joints. The form, orientation, and geometric characteristics of Cr3C2-NiCr friction surfaces are assessed as well and slipping curves are determined. The results show a standard deviation in the static CoF depending on nominal contact pressure, but it is not yet possible to establish a correlation with coating properties such as carbide grain size and geometrical parameters such as coating roughness.
Corrosion Protection of a 5xxx Series Aluminum Alloy by Cold Spray Process
Authors: Sridharan K. , Maier B. , Hauch B. , Devan D. 
Published: March 2024

Abstract
In this investigation, 5083 aluminum alloy coatings were deposited on substrates of the same material by high-pressure cold spraying. Spray trials were carried out using powders with size ranges of 5-20 µm and 20-44 µm, gas temperatures of 673 K and 773 K, and nitrogen and helium process gases. Coatings and coating-substrate interfaces were evaluated primarily by SEM and EDS, while XRD was used to examine coating stresses and oxidation effects. Corrosion protection was assessed by electrochemical potentiodynamic measurements in synthetic seawater and Knoop indentations tests were conducted as a measure of work-hardening and mechanical integrity of the coatings. Test results are presented and correlated with spray parameters.
Investigation on Microstructural & Mechanical Properties of Cold Sprayed & P/M Processed Composites
Authors: Chandanayaka T. , Azarmi F. 
Published: March 2024

Abstract
In this study, nickel-matrix composites reinforced with nickel-aluminide particles are produced by cold spraying and powder metallurgy techniques. A powder mixture of 80 vol% Ni and 20 vol% Ni3Al is used in both processes. Optical microscopy, SEM, and EDX analysis are used to evaluate the microstructural uniformity of the as-fabricated composites, while hardness and Young’s modulus are determined by microindentation tests. Microhardness tests are also conducted after each step of the P/M process in order to evaluate corresponding changes in hardness. The findings are presented and explained.
Comparison of Microstructures and Mechanical Properties between Thermal and Kinetic Sprayed Thick Fe Deposits on Fe-Si Alloy Sheets
Authors: Kim Jaeick , Bae Gyuyeol , Won Juyeon , Lee Changhee , Jun Teasung , Choi Jongkyo 
Published: March 2024

Abstract
In this study, plain carbon steel wire and pure iron powder are deposited on grit-blasted Fe-Si alloy substrates using thermal (electric arc, plasma, and HVOF) and kinetic spraying techniques. The coatings obtained were then heat treated. Coating microstructures and mechanical properties were investigated and compared focusing on oxidation, delamination, and Si dilution from the substrate to the coating.
Preparation and Characterization of TiO2 Scattering Layer for Plastic Dye-Sensitized Solar Cells by Vacuum Cold Spray
Authors: He X.-L. , Yang G.-J. , Li C.-X. , Li C.-J. , Fan S.-Q. 
Published: March 2024

Abstract
Plastic dye-sensitized solar cells (DSCs) are a promising photochemical solar technology owing to their light weight, flexibility, and suitability for low-cost roll-to-roll production. In order to improve cell efficiency, a light scattering layer was prepared on the surface of nanocrystalline (NC) TiO2 by vacuum cold spraying (VCS) at room temperature using submicron-sized TiO2 particles. The influence of the scattering layer and its connection with the underlying TiO2 was investigated to understand the improvement in cell efficiency. For comparison, two scattering layers were prepared by spray deposition using ethanol-based suspensions with either submicron Al2O3 or TiO2 particles. All three layers exhibited a higher light-reflecting capacity than the TiO2 nanocrystalline layer, although dark current test results showed that the biggest efficiency improvement was achieved in the NC-VCS-TiO2 cells.
Dust Explosion Properties of Aluminum, Titanium, Zinc and Iron Based Alloy Powders Used for Cold Spray
Authors: Sakata K. , Tagomori K. , Sugiyama N. , Sasaki S. , Shinya Y. , Nanbu T. , Kawashita Y. , Narita I. , Miyahara H. 
Published: March 2024

Abstract
In this study, the dust explosion properties of aluminum, titanium, zinc, and iron based alloy powders were evaluated by JIS Z 8818: “Test method for minimum explosible concentration of combustible dusts,” IEC 61241-2-3 (1994-09) Section 3: “Method for determining minimum ignition energy in dust-air mixtures,” and JIS Z 8817: “Test method for explosion pressure and rate of pressure rise of combustible dusts.” The test are described and the results are presented and discussed.
Design and Development of High-Pressure Warm Spray Gun
Authors: Katanoda H. , Sun B. , Ohno N. , Fukanuma H. , Kuroda S. , Watanabe M. , Ohashi O. 
Published: March 2024

Abstract
A new high-pressure warm spray gun was designed with the aim of increasing particle velocities to 1000 m/s for 30 µm Ti particle at 1000 °C or below. Nozzle geometry and combustion chamber pressure were optimized based on one-dimensional simulations. The flow rate of nitrogen gas injected into a mixing chamber was determined by calculation. The fuel injector was developed experimentally, its geometry optimized to spay small well-diffused droplets of kerosene into a 4 MPa chamber.
Mechanical Properties of Cold Sprayed Al Coatings Reinforced by Ceramics
Authors: Ko K.H. , Choi J.O. , Lee H. 
Published: March 2024

Abstract
This work investigates the effect of feedstock size on the hardness and wear resistance of metal-matrix composite coatings produced by cold spraying. Feedstocks consisting of Al and Al2O3 powders were prepared for the study. The feedstocks, which differ in regard to Al2O3 particle size (100, 50, 10 µm) and composition (25-50 vol%), were accelerated by compressed air through a Delaval-type nozzle positioned 10 mm from the target substrate. The morphology of the coating resembled that of an Al matrix with embedded Al2O3 particles. Optical microscopy showed that large Al2O3 particles (&gt; 50 µm) fractured into small pieces and embedded in the matrix. It is likely that some of the fragmented particles bounced off, rather than adhering. These collisions (tamping effect) increase coating hardness and density. In the case of the feedstock with 10 µm Al2O3, particle sizes were unchanged during spraying and the benefits of work hardening were not achieved.
Influence of Carrier Gas Composition on Microstructures and Mechanical Properties of Cold-Sprayed Titanium Coatings
Authors: Ichikawa Y. , Ogawa K. , Nose N. , Nomura Y. , Takahashi M. , Amano H. 
Published: March 2024

Abstract
This study investigates the effects of gas composition on cold-sprayed titanium coatings deposited under nine different spray conditions. Experiments show that higher levels of gas purity translate to higher particle velocities and measurable improvements in bending strength. The influence of gas temperature, pressure, and chemical composition is considered in the study along with interactions between carrier gases and sprayed particles. In addition to bending strength, the resulting coatings are assessed in terms of porosity and oxygen content.
Anisotropic Mechanical Properties of Cold Sprayed Copper Coatings
Authors: Watanabe Y. , Atsumi K. , Yamada M. , Fukumoto M. 
Published: March 2024

Abstract
Cold spraying is a promising process to fabricate functional coatings. Because of the solid-state particle deposition, the electrical and chemical properties of the coatings are similar to those of bulk materials. This is not the case with mechanical properties, however, which differ between the coating and bulk due to severe plastic deformation in the particles. The residual stress and bonding state of particles in cold-spray coatings are investigated in this study as to their influence on mechanical anisotropy. Bending tests on cold spray copper coatings show that loading direction has a significant effect, which may be related to the distribution of microvoids and pores. Traverse patterns and process gas temperature are also examined and are shown to play a role.
Splat Formation and Adhesion Mechanisms of Cold Gas Sprayed Al Coatings on Al2O3
Authors: Wielage B. , Drehmann R. , Grund T. , Rafaja D. , Schucknecht T. , Manygoats K. 
Published: March 2024

Abstract
In this study, aluminum is deposited by cold gas spraying on smooth and rough alumina substrates. SEM examination of single particle splats on polycrystalline Al2O3 suggests that mechanical interlocking is the primary bonding mechanism for cold gas sprayed metals on rough ceramic surfaces. Coating cross-sections on monocrystalline, atomically smooth sapphire substrates were examined by means of high-resolution TEM, revealing nanosized Al grains close to the interface, which could be an indicator of recrystallisation induced by local heating and the deformation energy stored in the particle during impact.
Analysis of Thermal History and Residual Stress in Cold Sprayed Coatings
Authors: Arabgol Z. , Assadi H. , Schmidt T. , Gärtner F. , Klassen T. 
Published: March 2024

Abstract
It is generally believed that residual stresses in cold spray coatings are caused by particle impact and deformation and are hence predominantly compressive, as opposed to thermal spraying where thermal effects, particularly solidification, play the lead role. This study aims to provide a preliminary review of this notion through finite element analysis, distortion measurements on copper-coated steel, and the consideration of thermal history. The dimensions and elastic properties of the coating and substrate are key factors in the study along with heat input. Based on the review, a simple model is proposed to predict the final state of residual stress and distortion in flat surfaces coated by cold spraying.
Multi-Scale Analysis between Microstructure and Absorbing Performance of Thermal Sprayed Fe-(β-SiC/SiO2) Coatings
Authors: Yuan Xiaojing , Zha Bailin , Wang Hangong 
Published: March 2024

Abstract
This paper describes how effective medium theory and fractal analysis are used to investigate nonlinear microstructure-property relationships in HVOF-sprayed composite coatings produced from nano Fe-(β-SiC/SiO2) agglomerate powders in order to optimize microwave absorption performance. The powder used in the study was prepared by spray granulation and deposited on Fe substrates. The microstructure of the powder and coatings was examined by SEM, the phase structure was determined by XRD analysis, and electrical permittivity and permeability were measured. To simplify calculations, electromagnetic absorption phases in the coating were assumed to be periodically distributed cubes. The results of the study indicate that multi-fractal diffraction in the coating microstructure facilitates the absorption of microwaves and is optimized when the mass fraction of nano βSiC in the composite is 28 wt%.
Influence of Surface Contamination on the Adhesion Strength of HVOF Coatings
Authors: Barr J. , Estrada C. , White B. 
Published: March 2024

Abstract
Base metal surfaces are typically prepared for thermal spraying by chemically cleaning followed by grit blasting. In common practice, HVOF coatings are applied within 2-4 h or the entire cleaning process is repeated to prevent in-service adhesion failures. This study was initiated to assess the effect of long wait times on the adhesion strength of WC-Ni coatings. Test coupons were chemically cleaned, grit blasted, and then set out in shop conditions for up to 48 hrs. Some were also subjected to different forms of contamination including dirty fingerprints, grease, penetrating oil, surface rust, tape residue, and paint. Pull test and metallographic examination results show that none of the contaminants had an influence on the adhesion strength of the HVOF coatings.
Development and Characterization of B4C Reinforced Detonation Sprayed Al Coatings
Authors: Tillmann W. , Hollingsworth P.S. , Fischer G. , Nellesen J. 
Published: March 2024

Abstract
This paper describes the development of detonation-sprayed aluminum-matrix composite coatings reinforced with boron carbide. The goal is to achieve a homogeneous coating structure with low porosity, low oxide content, and high concentration of embedded carbides. Tensile tests of various types were conducted and different stages of deformation were analyzed using micro computed tomography, a 3D imaging technique that reveals the formation of cracks in real time.