Corrosion and Oxidation Behavior of a Fe-Al-Mn-C Duplex Alloy

The low-density steels represent a topic of great interest within the scientific world because of the great demand from the steel market of increasingly lighter materials, also featured by an optimal mix of the mechanical properties. In this work, the corrosion and hot oxidation resistance of a Fe-15%Mn-9.5%Al-6.5%Ni-1%Cr-0.43%C were analyzed and related to the microstructural features. The material behavior was analyzed both in the as-cast and in the heat-treated state. For the corrosion test, the experimental plan was fulfilled using four different concentrations of HCl and four temperatures. In the case of hot oxidation resistance, the exposure time and the temperature effects were evaluated. The corrosion resistance in HCl was comparable to the stainless steel, and the iso-corrosion curves showed excellent resistance of the 1300 °C solution-treated material, especially at low temperatures, but it is also good at high temperatures due to the hot oxidation.

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Crystallographic Differences of Metastable NI2MO in a NI-MO-AL Superalloy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600000672 ◽

1980 ◽

Vol 38 ◽

pp. 158-159

Author(s):

Michael M. Kersker ◽

E. A. Aigeltinger ◽

J. J. IIren

Keyword(s):

Mechanical Properties ◽

Air Cooling ◽

Solution Treated ◽

Heat Treated ◽

Metastable Compounds ◽

Rapidly Solidified

Ni-rich alloys based on approximate ternary composition Ni-8Mo-15A1 (at%) are presently under investigation in an attempt to study the contribution, if any, of the profusion of Mo-rich NixMo metastable compounds that these alloys contain to their excellent mechanical properties. One of the alloys containing metastable NixMo precipitates is RSR 197 of composition Ni-8.96Mo-15.06A1-1.98Ta-.015Yt. The alloy was prepared at Pratt and Whitney Government Products Division, West Palm Beach, Florida, from rapidly solidified powder. The powder was canned under inert conditions and extruded as rod at 1315°C. The as-extruded rod, after air cooling, was solution treated at 1315°C for two hours, air cooled, and heat treated for one hour at 815°C, followed again by air cooling.

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Effect of Heat Treatment on the As-Cast Microstructure and Hardness of NiSi3B2 Alloy

Metals ◽

10.3390/met11040539 ◽

2021 ◽

Vol 11 (4) ◽

pp. 539

Author(s):

Gonçalo M. Gorito ◽

Aida B. Moreira ◽

Pedro Lacerda ◽

Manuel F. Vieira ◽

Laura M. M. Ribeiro

Keyword(s):

Heat Treatment ◽

Elevated Temperatures ◽

Casting Process ◽

X Ray Diffraction ◽

Heat Treated ◽

Energy Dispersive Microanalysis ◽

Eutectic Constituent ◽

Backscattered Electron ◽

Corrosion And Oxidation ◽

Cast Microstructure

Cast Ni-Si-B alloys have the potential for high-temperature applications because of their high resistance to wear, impact, corrosion, and oxidation at elevated temperatures due to an appropriate balance of hard phases and austenite that ensures a good compromise between toughness and hardness. In this work, NiSi3B2 specimens, fabricated by the lost-wax casting process, were investigated. Given the complex multiphase cast microstructure, a differential scanning calorimeter (DSC-TGA) analysis was employed to characterize the reactions that occur during solidification and the resulting phases were characterized using scanning electron microscopy (SEM), with energy-dispersive microanalysis (EDS) and backscattered electron (BSE) image and X-ray diffraction (XRD). Due to the presence of hard phases, machining of the Ni-Si-B components can pose additional difficulties. Therefore, the conditions of the solution heat treatment, which might lead to the homogenization of the microstructure, consequently improving its machinability, were also investigated. The results of the heat-treated samples indicated that the dissolution of the eutectic constituent is accompanied by a significant decrease in the hardness (approximately 17%). It is important to emphasize that the solution heat treatments carried out reduced the hardness without affecting the percentage of borides, which will allow improving the machinability without adversely affecting the alloy performance in service.

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Oxidation-Resistance of (Ti,Al,Cr,Y)N Coatings Prepared by Arc Ion Plating

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.177.338 ◽

2010 ◽

Vol 177 ◽

pp. 338-341

Author(s):

Ming Sheng Li ◽

Yong Zhong Fan ◽

Shu Juan Zhang

Keyword(s):

Oxidation Resistance ◽

Crystal Size ◽

Substrate Bias ◽

Compressor Blades ◽

Arc Ion Plating ◽

Ion Plating ◽

Cr Content ◽

Heat Treated ◽

Aero Engine ◽

Engine Compressor

In this study, composite metastable (Ti0.49Al0.49Y0.02)N, (Ti0.44Al0.44Cr0.1Y0.02)N and (Ti0.34Al0.34Cr0.3Y0.02)N coatings were respectively deposited on a wrought martensite steel 1Cr11Ni2W2MoV for aero-engine compressor blades by arc ion plating technique with a pulse substrate bias. All the coatings have B1NaCl phase structure with a (220) preferred orientation and dense structures. The introduction of chromium into the coatings gave rise to a minute shrinkage of crystal lattice and a decrease of crystal size. Annealed at 800°C, Oxidation-resistance of the coatings improved with increased Cr content. But heat-treated at 900°C, the incorporation of Cr gave rise to obvious decrease of oxidation-resistance.

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Microstructure and Aging Behavior of Al-0.2wt%Zr Alloy Heavily Deformed by ARB Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.584-586.728 ◽

2008 ◽

Vol 584-586 ◽

pp. 728-733 ◽

Cited By ~ 1

Author(s):

Takatoshi Sato ◽

Daisuke Terada ◽

Nobuhiro Tsuji

Keyword(s):

Grain Size ◽

Microstructural Evolution ◽

Coarse Grain ◽

Aging Behavior ◽

Roll Bonding ◽

Solution Treated ◽

Ultrafine Grained ◽

Mean Grain Size ◽

Treated State ◽

Zr Alloy

An Al-0.2wt%Zr alloy was severely deformed up to a strain of 8.0 by accumulative roll bonding (ARB) process, started from the solution-treated state. The microstructural evolution during ARB and its aging behavior were investigated. With increasing the number of ARB cycles, Vickers hardness of the specimens increased and reached to a constant value. The microstructural evolution during the ARB could be understood in terms of grain subdivision. The ultrafine grained (UFG) materials whose mean grain size was 0.4 -m were obtained by 10-cycle ARB process. In aging of the ARB processed specimens at high temperatures above 673K, the UFG microstructures quickly coarsened. On the other hand, it was suggested that the precipitation behaviors of the ARB specimen at 623K were quite unique and completely different from those of the conventionally solution-treated material with coarse grain size.

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Experimental Investigation of Various Chip Parameters during Machining of the Ti25Nb3Mo3Zr2Sn Beta Titanium Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.622-623.366 ◽

2012 ◽

Vol 622-623 ◽

pp. 366-369 ◽

Cited By ~ 1

Author(s):

Rizwan Abdul Rahman Rashid ◽

Shou Jin Sun ◽

Gui Wang ◽

Matthew Simon Dargusch

Keyword(s):

Titanium Alloy ◽

Chip Thickness ◽

Shear Angle ◽

Beta Titanium Alloy ◽

Solution Treated ◽

Beta Titanium ◽

Heat Treated ◽

Wide Range ◽

Thickness Shear ◽

Cutting Speeds

Machining of Ti25Nb3Mo3Zr2Sn beta titanium alloy is carried out under two different heat treatments, solution treated, and solution treated and aged conditions. The chips formed after machining were cold mounted, polished and etched to reveal their microstructures. Different chip parameters such as average chip thickness, shear angle, undeformed chip length, and distance between serrations were measured and reported for both the heat treated samples for a wide range of cutting speeds, ranging from 5 m/min to 175 m/min. The results obtained were explained in terms of the heat treatment (hardness) of the samples and the cutting speeds.

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Potentiostatic Polarization of Inconel X-750

CORROSION ◽

10.5006/0010-9312-28.9.331 ◽

1972 ◽

Vol 28 (9) ◽

pp. 331-336 ◽

Cited By ~ 3

Author(s):

B. L. TROUT ◽

R. D. DANIELS

Keyword(s):

Anodic Polarization ◽

Chloride Ion ◽

Ion Concentration ◽

Anodic Passivation ◽

Solution Treated ◽

Heat Treated ◽

Polarization Characteristics ◽

Potentiostatic Polarization

Abstract The anodic polarization characteristics of Inconel X-750 Alloy in two heat treated conditions, (1) solution treated and (2) solution treated and aged, were examined for sensitivity to temperature and to chloride ion concentration. The effects of microstructure and environment on the anodic passivation behavior of this alloy are correlated and discussed.

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Phase and Morphology of Carbides in ASTM F75 Co-Cr-Mo-C Alloys Formed at 1473 to 1623 K

Materials Science Forum ◽

10.4028/www.scientific.net/msf.654-656.2176 ◽

2010 ◽

Vol 654-656 ◽

pp. 2176-2179 ◽

Cited By ~ 3

Author(s):

Shingo Mineta ◽

Alfirano ◽

Shigenobu Namba ◽

Takashi Yoneda ◽

Kyosuke Ueda ◽

...

Keyword(s):

Carbon Content ◽

Complete Dissolution ◽

Stripe Pattern ◽

Precipitate Dissolution ◽

Solution Treated ◽

Heat Treated ◽

Cast Alloys ◽

M23c6 Type ◽

Type Carbide ◽

Astm F75

The phase and morphology of precipitates in heat-treated Co-28Cr-6Mo-xC (x = 0.12, 0.15, 0.25, and 0.35mass%) alloys were investigated. The as-cast alloys were solution-treated in the temperature range of 1473 to 1623 K for 0 to 43.2 ks. Complete precipitate dissolution was observed in all four alloys, each of which had different carbon contents. The holding time for complete dissolution was greater for alloys with greater carbon content. The curve representing the boundary between the complete- and incomplete-dissolution conditions for each alloy is C shaped. Under the incomplete precipitate dissolution conditions of the Co-28Cr-6Mo-0.25C alloy, an M23C6 type carbide and a π-phase (M2T3X type carbide with β-Mn structure) were observed at 1548 to 1623 K, and starlike precipitates with a stripe pattern and with a dense appearance were both observed; the former comprised the M23C6 type carbide + γ-phase, and the latter was the π-phase. In contrast, only a blocky-dense M23C6 type carbide was observed at 1473 to 1523 K.

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Microstructures and Properties of Ti-25Nb-15Zr Alloy for Spectacle Frame

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.727.191 ◽

2017 ◽

Vol 727 ◽

pp. 191-195

Author(s):

Xi Qun Ma ◽

Zhen Tao Yu ◽

Han Yuan Liu ◽

Jun Cheng ◽

Jin Long Niu ◽

...

Keyword(s):

Single Phase ◽

Complete Recovery ◽

Elastic Behavior ◽

Shape Memory Property ◽

Good Shape ◽

Fine Grain ◽

Solution Treated ◽

Recovery Strain ◽

Heat Treated ◽

Spectacle Frame

Mechanical properties and microstructures of a new β Ti-25Nb-15Zr alloy for spectacle frame were studied. The results show that the optimum cold rotary swaging reduction of the alloy is between 50% and 70%. The wire of 3mm in diameter exhibited an equiaxed microstructure consisting only β single phase and fine grain with less than 10mm size when the alloy is heat treated at 1003K for 1.8Ks. While it has good shape memory property, and the maximum complete recovery strain was up to 3% at room temperature. At the same time, the flattened frame legs were solution-treated to improve their elastic behavior, so the residual strain was completely or partly recovered due to transformation of the microstructure.

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Enhanced Formability of Age-Hardenable Aluminium Alloys by Incremental Forming of Solution-Treated Blanks

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.549.164 ◽

2013 ◽

Vol 549 ◽

pp. 164-171 ◽

Cited By ~ 5

Author(s):

Amirahmad Mohammadi ◽

Hans Vanhove ◽

Albert van Bael ◽

Joost R. Duflou

Keyword(s):

Precipitation Hardening ◽

Incremental Forming ◽

Natural Aging ◽

Solution Treated ◽

Treatment Conditions ◽

Heat Treated ◽

Initial Hardness ◽

Aa 2024 ◽

Cold Worked ◽

Pre Treatment

The influence of thermal pre-treatment on the formability of a precipitation-hardening aluminium alloy AA-2024 has been studied for three different heat treatment conditions: annealed (O-temper), solution treated and quenched (W-temper) and solution heat treated, quenched and then cold worked (T-temper).The maximum draw angle has been determined and the geometrical accuracy of specific SPIF formed parts has been compared. It is found that the maximum forming angles of the blank formed in O-temper and W-temper conditions show a respective 41% and 32% increase to those of the T-temper condition (initial blank).The hardness of the material reduces significantly after annealing, while SPIF parts formed from W-temper blanks regain their initial hardness after natural aging.

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