Oxidation Resistance and Microstructure Evaluation of a Polymer Derived Ceramic (PDC) Composite Coating Applied onto Sintered Steel

Powder metallurgy is a competitive technology to produce ferrous near net shape parts for diverse engineering applications. However, their inherent porosity increases the susceptibility to oxidation and sealing their surface is mandatory to avoid premature degradation. Alongside, polymer derived ceramics (PDCs), such as silicon-carbonitride, have drawn attention concerning their high temperature and chemical stability. However, PDCs undergo volume shrinkage during ceramization that leads to defect formation. The shrinkage can be compensated by the addition of fillers, which are also capable of tailoring the ceramic resulting properties. This work evaluates the processing of PDC-based coatings loaded with ZrO2 and glass fillers to compensate for the shrinkage, densify the coating and seal the sintered steel surface. Therefore, polymeric slurries were sprayed onto sintered steel substrates, which were pyrolyzed at different temperatures for microstructural and oxidation resistance evaluation. Microstructural modifications caused by the enhanced glass viscous flow during pyrolysis at 800 °C resulted in more homogeneous, dense and protective coatings, which reduced the mass gain up to 40 wt% after 100 h of oxidation at 450 °C in air in comparison to the uncoated substrate. Moreover, no macrocracks or spallation were detected, confirming the feasibility of PDC composite barrier coatings for sintered steels.

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High-Temperature Oxidation Resistance of PDC Coatings in Synthetic Air and Water Vapor Atmospheres

Molecules ◽

10.3390/molecules26082388 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2388

Author(s):

Milan Parchovianský ◽

Ivana Parchovianská ◽

Peter Švančárek ◽

David Medveď ◽

Mateus Lenz-Leite ◽

...

Keyword(s):

Water Vapor ◽

Bond Coat ◽

Protective Coatings ◽

Temperature Oxidation ◽

Oxidative Resistance ◽

Strong Adhesion ◽

Different Temperatures ◽

Water Vapor Atmosphere ◽

Scratch Tests ◽

Steel Substrates

This work is aimed at the development and investigation of the oxidation behavior of ferritic stainless-steel grade AISI 441 and polymer-derived ceramic (PDC) protective coatings. Double-layer coatings of a PDC bond coat below a PDC top coat with glass and ceramic passive fillers’ oxidative resistance were studied at temperatures up to 1000 °C in a flow-through atmosphere of synthetic air and in air saturated with water vapor. Investigation of the oxide products formed at the surface of the samples in synthetic air and water vapor atmospheres, at different temperatures (900, 950, 1000 °C) and exposure times (24, 96 h) was carried out on both uncoated steel and steel coated with selected coatings by scanning electron microscopy (SEM) and X-Ray diffraction (XRD). The Fe, Cr2O3, TiO2, and spinel (Mn,Cr)3O4 phases were identified by XRD on oxidized steel substrates in both atmospheres. In the cases of the coated samples, m- ZrO2, c- ZrO2, YAG, and crystalline phases (Ba(AlSiO4)2–hexacelsian, celsian) were identified. Scratch tests performed on both coating compositions revealed strong adhesion after pyrolysis as well as after oxidation tests in both atmospheres. After testing in the water vapor atmosphere, Cr ions diffused through the bond coat, but no delamination of the coatings was observed.

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Improvement of oxidation resistance of Nb–Ti–Si based alloys with additions of Al, Cr and B at different temperatures

Progress in Natural Science Materials International ◽

10.1016/j.pnsc.2021.04.006 ◽

2021 ◽

Author(s):

Guangxin Sun ◽

Lina Jia ◽

Zhen Hong ◽

Guangxu Liu ◽

Hu Zhang

Keyword(s):

Oxidation Resistance ◽

Different Temperatures

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Oxidation resistance of nickel-based superalloy Inconel 600 in air at different temperatures

Rare Metals ◽

10.1007/s12598-018-1148-1 ◽

2018 ◽

Author(s):

Dong-Sheng Li ◽

Guang Chen ◽

Dan Li ◽

Qi Zheng ◽

Pei Gao ◽

...

Keyword(s):

Oxidation Resistance ◽

Inconel 600 ◽

Nickel Based Superalloy ◽

Different Temperatures

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Improving Tribological Characteristics of Hip Prostheses Using Biocompatible Nanocoatings

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.741.67 ◽

2013 ◽

Vol 741 ◽

pp. 67-72 ◽

Cited By ~ 3

Author(s):

Gheorghe I. Gheorghe ◽

Liliana Laura Badita

Keyword(s):

Hip Prosthesis ◽

Protective Coatings ◽

Scratch Resistance ◽

Hip Prostheses ◽

Force Microscopy ◽

Tin Coatings ◽

Femoral Heads ◽

Before And After ◽

Tin Thin Films ◽

Steel Substrates

Total hip prosthesis (THP) is the most success of the 20th century in orthopaedic biomedical engineering. However due to difficult conditions within the human body its durability is generally limited to 15-16 years. THP is a bio-tribosystem, on which many mechanical, thermal, chemical and biological factors act. This paper presents the results of an analysis regarding the topography and tribological parameters of femoral heads structures before and after TiN coating. We report on the synthesis of TiN thin films on steel substrates by pulsed laser deposition (PLD) method for improving the mechanical characteristics of the structures. Adhesion resistance of the coating on the sub-layer was evaluated by scratching tests accompanied by Optical Microscopy (OM), Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). As a principal result, this work points out that TiN protective coatings deposited by PLD technique with the maximum number of pulses can represent an alternative technology to ensure adhesion and scratch resistance of TiN coatings on femoral heads.

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Oxidation Behaviors of TiB2-TiCX and TiB2-TiCX/15SiC Ceramics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.105-106.179 ◽

2010 ◽

Vol 105-106 ◽

pp. 179-183 ◽

Cited By ~ 3

Author(s):

De Gui Zhu ◽

Hong Liang Sun ◽

Yu Shu Wang ◽

Liang Hui Wang

Keyword(s):

Oxidation Resistance ◽

Effective Temperature ◽

Hot Isostatic Pressing ◽

Ceramic Composites ◽

Optical Micrograph ◽

Different Temperatures ◽

The Mean ◽

Mean Time ◽

Oxidation Behaviors

Fully dense samples of TiB2-TiCX and TiB2-TiCX/15SiC ceramic composites were fabricated by in-situ synthesis under hot isostatic pressing from TiH2, B4C and SiC powders. Their oxidized behaviors at different temperatures were tested. Optical micrograph studies and thermo-gravimetric analyses show that the highest effective temperature of oxidation resistance is 700°C for TiB2-TiCX, and 1100°C for TiB2-TiCX/15SiC. The weight gain of TiB2-TiCX/15SiC below 1100°C is quite low, and it rises up suddenly when the temperature reaches 1200°C. Thus, the highest effective temperature of oxidation resistance is 1100°C for TiB2-TiCX/15SiC. The oxidation dynamic curves of TiB2-TiCX/15SiC ceramics accord with the parabola’s law. The activation energy of TiB2-TiCx/15SiC (189.87kJ.mol-1) is higher than that of TiB2-TiCx (96.44kJ.mol-1). In the oxidation process of TiB2-TiCx/15SiC, TiB2 reacts with oxygen and generates TiO2 and B2O3 at first. A layer of whole homogeneous oxide film cannot be formed, in the mean time, the oxidation of TiC begins. When temperature goes up to 1000°C, TiC phase is totally oxidized. SiC is oxidized to SiO2 at about 900°C, Meanwhile, TiO2 forms denser film than B2O3, which grows and covers the surface of the material, and gives better property of oxidation resistance.

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Thermal Stablility and Oxidation Resistance of CrAlSiN Nano-Structured Coatings Deposited by Lateral Rotating Cathode Arc

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.447-448.725 ◽

2010 ◽

Vol 447-448 ◽

pp. 725-729 ◽

Cited By ~ 6

Author(s):

Jhun Yew Cheong ◽

Xing Zhao Ding ◽

Beng Kang Tay ◽

Xian Ting Zeng

Keyword(s):

Oxidation Resistance ◽

Deposition Process ◽

Surface Oxide Layer ◽

Ambient Atmosphere ◽

Temperature Oxidation ◽

X Ray ◽

Good Oxidation Resistance ◽

Before And After ◽

Different Temperatures ◽

Cathode Arc

In this paper, CrAlSiN coatings are deposited by a lateral rotating cathode arc technique. The high temperature oxidation behaviors of these coatings are studied in ambient atmosphere at temperatures ranging from 800°C-1000°C for an hour. The ternary TiAlN coating is used as the benchmark in this study. The surface morphology and chemical composition of the coating samples before and after oxidation at different temperatures are analyzed by scanning electron microscopy (SEM) equipped by energy dispersive X-ray spectrometer (EDX), glow discharge optical spectrometry (GDOS) and X-ray diffraction (XRD). The CrAlSiN coatings show much better oxidation resistance than the TiAlN coatings. TiAlN starts to oxidize from 800oC and forms a complete surface oxide layer after oxidation at 1000oC for an hour. However, CrAlSiN shows a relatively good oxidation resistance below 1000oC and only is oxidized to form a thin oxide scale with a thickness of 0.3 µm at 1000oC for one hour. It is found that the oxidation of both coatings is triggered from the surface metallic droplets generated by the arc deposition process.

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Properties of Electrospark Deposited Cr Coatings on AISI H13 Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.472-475.288 ◽

2012 ◽

Vol 472-475 ◽

pp. 288-292

Author(s):

Cean Guo ◽

Jian Zhang ◽

Li Yang ◽

Wei Zhou ◽

Hong Hui Sun

Keyword(s):

High Temperature ◽

Oxidation Resistance ◽

High Temperature Oxidation ◽

Wear Behavior ◽

H13 Steel ◽

Electrospark Deposition ◽

Temperature Oxidation ◽

Aisi H13 Steel ◽

Aisi H13 ◽

Steel Substrates

Cr coatings were deposited on AISI H13 steel substrates by means of electrospark deposition (ESD). The coatings were characterized in terms of their microstructure, hardness, friction and wear behavior and high-temperature oxidation resistance. Micro-indentation and tribometer testers were employed to measure the mechanical properties of Cr coatings and AISI H13 steel. The results showed that the hardness of the coatings ranged from 600 to 660 HV, with a higher value than that of AISI H13 steel (510 HV). The coefficient of steady-state friction of the coatings against 45-carbon-steel balls ranged from 0.23 to 0.27, with a lower value than that of AISI H13 steel (0.62-0.68). The isothermal oxidation behavior of the coatings at 850°Cwas studied in comparison with AISI H13 steel substrates. The results indicated that Cr coatings substantially increase the high-temperature oxidation resistance of AISI H13 steel and the oxidation process was retarded mainly by the presence of a Cr2O3 oxide scale on the coatings at 850°C for 100 hours.

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ENHANCING HIGH-TEMPERATURE OXIDATION RESISTANCE OF TITANIUM ALLOY WITH KF110-B4C-Ag THROUGH LASER TECHNOLOGY

Surface Review and Letters ◽

10.1142/s0218625x22500032 ◽

2021 ◽

Author(s):

ZHAO ZHANG ◽

JIANING LI ◽

ZHIYUN YE ◽

CAINIAN JING ◽

MENG WANG ◽

...

Keyword(s):

Titanium Alloy ◽

High Temperature ◽

Oxidation Resistance ◽

High Temperature Oxidation ◽

Mass Gain ◽

Temperature Oxidation ◽

Laser Technology ◽

X Ray ◽

Ta15 Titanium Alloy ◽

Oxidation Resistant

In this paper, the high-temperature oxidation resistant coating on the TA15 titanium alloy by laser cladding (LC) of the KF110-B4C-Ag mixed powders was analyzed in detail. The scanning electron microscope (SEM) and energy dispersive X-ray spectrometer (EDS) images indicated that a good metallurgy bond between the fabricated coating/TA15 was formed; also the fine/compact microstructure was produced after a cladding process. The oxidation mass gain of TA15 was higher than that of the coating after LC process, which were 3.72 and 0.91[Formula: see text]mg[Formula: see text]cm[Formula: see text], respectively, at 60[Formula: see text]h, greatly enhancing the high temperature oxidation resistance.

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Influence of Nitrogen on Oxidation Resistance of Automotive Steel Grades

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.835.83 ◽

2020 ◽

Vol 835 ◽

pp. 83-92

Author(s):

Saeed Ghali ◽

Mamdouh Eissa ◽

Hoda El-Faramawy ◽

Azza Ahmed ◽

Fathy Baiomy ◽

...

Keyword(s):

Oxidation Resistance ◽

Stainless Steels ◽

Oxidation Process ◽

Diffusion Mechanism ◽

Solution Treatment ◽

Mass Gain ◽

Optical Microscope ◽

Partial Replacement ◽

Steel Grades ◽

Automotive Steel

With the objective of partial and total replacement of nickel by nitrogen in austenitic exhausted valve steel X45CrNiW18-9, a program of work with series of experimental heats was designed. Experimental heats were carried out in 10 Kg. induction furnace under nitrogen pressure. The chemical composition of produced stainless steels was determined. The produced automotive steel grades were forged. The nitrogen contents were determined. The produced forged stainless steels were subjected to solution treatment at 1050 °C for 1 hour, followed by water cooling. Isothermal oxidation test is used to detect the behavior of new grades at different temperatures in air for solution treated stainless steels. The mass gain was measured for samples exposed to air at temperatures (500 °C, 600 °C, 700 °C, 800°C) for different time intervals, up to 1000 hrs. The oxide layer thickness for two selected steels was investigated by using optical microscope. XRD was used to detect types of oxides which are formed during oxidation process at 800 °C for 1000 hrs for represented investigated exhausted valve steels. Scanning Electron Microscope was used to make scan steels surface, after heating at 500 °C and 800 °C for l000hr. The mechanism of the oxidation of developed steels was investigated. It was found controlled by diffusion mechanism and the kinetic of oxidation process is parabolic. Oxidation rate of the investigated stainless steels for times, up to 8 h and between 200 andl000 h, at all investigated temperatures (500 °C - 800 °C), is parabolic and the oxidation is diffusion controlled. While in the time region 10 to 200 h, it obeys combined mechanisms. Partial replacement of nickel, by nitrogen, improves the oxidation resistance in air at temperature range 500°C - 800°C.

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