AMPP Store - Products tagged with 'microstructure'

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Corrosion of Additively Manufactured Stainless Steel 304L in Chloride Solution

Product Number: 51324-21159-SG

Author: Leila Saberi; Mehdi Amiri

Publication Date: 2024

$40.00

Although there have been major strides in understanding the influence of additively manufacturing (AM) on mechanical properties such as tensile and fatigue, the understanding of the corrosion performance of AM-produced metals and alloys remains in its infancy. The corrosion performance and mechanical properties of AM metals are significantly influenced by their unique microstructural features that are highly dependent on the build parameters. These features include surface roughness, porosity, grain directionality, residual stresses, oxides, atypical inclusions, and sub-structures, to name a few. Such microstructural/defect features are distinct in comparison with those of cast or wrought alloys and span many orders of magnitude in length scale. Consequently, AM plays a significant role in corrosion performance. In this paper, the corrosion of additively manufactured stainless steel 304L (AM SS304L) in 5% NaCl solution is studied. The purpose of this research is to understand the correlation between microstructural/defect features and corrosion properties. The effects of surface roughness, surface porosity, and build orientation on corrosion and pitting potentials are investigated. All these features show significant impacts on corrosion performance of AM SS304L. Detailed microstructural and elemental analyses are performed to further understand the interrelation between microstructural/defect features and corrosion properties.

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Corrosion Properties of Ni-Al Bronze and it’s Main Alloying Elements - Effect of pH

Product Number: 51317--9306-SG

ISBN: 9306 2017 CP

Author: Hedda Krogstad

Publication Date: 2017

$20.00

The work is mainly focused on the corrosion mechanism at low pH (>4) and the order of which the discontinuous and continuous intermetallic phases dissolve. Compositions of each phase, and the area ratio between intermetallic phases and the alpha matrix have been calculated as an average of 20 measurements.

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Corrosion Studies of Novel Nickel-Base Alloys in Molten Chloride Salts

Product Number: 51324-21199-SG

Author: Harjot Singh; Diego Ochoa; Michael Kloesel; Vilupanur Ravi; Boateng Twum Donkor

Publication Date: 2024

$40.00

Molten salts are being considered for use in a new generation of nuclear reactors. Therefore, any materials selection process necessarily involves corrosion studies to understand the compatibility between the salts of interest and the materials of construction. This project investigated the corrosion behavior of novel Ni-base superalloys in molten chloride salt mixtures at 750°C for 200 hours in an inert atmosphere. Alloy response to the molten salt was examined through mass loss per unit area, analysis of surface phases and microstructural examination of the alloy cross-section along with elemental analysis. The role of critical alloying elements in alloy corrosion behavior was related to the material response to the molten salt. Alloy 6, an aluminum-containing alloy was the most corrosion resistant while Alloy 7, containing titanium additions, also did well. In the absence of these critical alloying elements, Alloy 4, proved to be the least corrosion resistant.

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Evaluation of the relationship between passivity and microstructure in austenitic stainless steel, the Point defect perspective

Product Number: 51323-19434-SG

Author: Raymundo Case, Homero Castaneda, Yuan Ding, Adnan Khan, M. L Cedeno- Vente, Gabriela Pena

Publication Date: 2023

$20.00

Additive manufacturing (AM), commonly referred to as 3D printing, offers advantages over traditional
production methods, such as quick prototyping, short production runs and intricate, thin section,
microfluidic, variable composition, and low-waste designs. These exciting features are accompanied by
new challenges, such as higher costs, the possibility of variable quality, and inherently anisotropic
properties.

Existing AM technologies include 3D printing, rapid prototyping (RP), direct digital manufacturing (DDM),
selective laser melting (SLM), and direct metal laser Sintering (DMLS).

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Examination Of A Ferritic Martensitic Steel Following Irradiation And High Temperature Water Corrosion

Product Number: 51322-18127-SG

Author: Ronald N. Clark, Tomas Martin, Dong Liu, Kun Mo, Jean-Charles Eloi, Robert Burrows, Sean Davis, David Kumar, Chris Harrington, Chris Jones

Publication Date: 2022

$20.00

Nuclear energy currently contributes approximately 10 % of the worldwide energy mix.¹ Nuclear energy generation is a form of low-carbon electricity, typically run as base-load, which alongside renewables can help nations toward climate change goals. Nuclear fission thermal reactors make up the majority of the reactors operating today. Nuclear fusion on the other hand is a promising alternative which produces less radioactive waste and does not have a reliance on the finite source of uranium fuel. Eurofer-97, a reduced activation ferritic-martensitic (RAFM) steel, will be used as a structural material for fusion reactors. The earliest literature reference to RAFM steels originated from 1994 by Abe et al.² One option for the European demonstration fusion reactor (DEMO) is to use a water-cooled lead-lithium (PbLi) breeder blanket (WCLL BB) design for heat extraction. Breeder blankets will be used to generate a source of tritium, for the fusion reaction with deuterium.

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Failure Analysis of Reactor Effluent Air Cooler (REAC) in a Hydrocracker Unit

Product Number: 51314-3730-SG

ISBN: 3730 2014 CP

Author: Surajit Ghosal

Publication Date: 2014

$0.00

A major fire in a Reactor Effluent Air Cooler (REAC) of the Hydrocracker Unit (HCU). Visual inspection was made on the failed portion. Metallurgical investigation, macrostructural and microstructural analysis, Scanning Electron Microscopy, and Energy Dispersive x-ray Spectroscopy was conducted on the failed air cooler.

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Failure of Cast Duplex Stainless Steel Valves Due to Improper Microstructure

Product Number: 51324-20759-SG

Author: K. Ravindranath; B. Al-Wakaa; A. Ali; Ahmad Al-Swaha; Salem Al-Qahtani

Publication Date: 2024

$40.00

Cast duplex stainless steels are popularly used in the petroleum industry due to their good corrosion resistance and mechanical properties. One of the applications of cast duplex stainless steels in the petroleum industry is in the manufacture of valves in corrosive service. The good properties of duplex stainless steels are attributed to their balanced microstructure containing austenite and ferrite phases. The balanced microstructure in the duplex stainless-steel components is achieved by the optimum heat treatment and manufacturing process. Improper cooling during manufacturing or accidental exposure of the component to high temperatures can induce the precipitation of secondary phases in the microstructure of duplex stainless steel, which can seriously influence the corrosion resistance and mechanical properties. The paper deals with the failure investigation of the first-generation cast duplex stainless steel valves that failed in a short duration of service. The microstructure of the failed valve was characterized by optical and scanning electron microscopy. The effect of the microstructure on the mechanical properties was assessed by hardness measurements, tensile testing, and impact toughness testing. The study indicated that the properties of the duplex stainless-steel valves were affected due to the precipitation of secondary phases and the root cause of the failure was embrittlement caused by the precipitated secondary phases.

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Field Metallography and Replication on Liquefied Natural Gas Assets: Non-Destructive Metallurgical Testing to complement other regular Non-Destructive Tests

Product Number: 51320-15140-SG

Author: Anil Kumar Chikkam, Mehrooz Zamanzadeh, Sunil Kumar Pulagam, Ganesh P, Dhandabani, Bangaru Murali, Jeevanandam Shanmugam

Publication Date: 2020

$20.00

During plant shutdown maintenance, some components cannot be removed out of service immediately for metallurgical examination due to high cost involved and loss of production hours. The best alternative is to replicate the lab based metallography work under the field conditions. Field Metallography and Replication (FMR) also known as in-situ metallography is a powerful non-destructive test (NDT) tool used to examine the microstructure of the component when it is still in service. Moreover, FMR is also used to study the microstructural alterations for the fitness for service assessment.

This paper provides case studies of materials in Natural Gas Processing facility where FMR was used as an NDT tool without sectioning the component. This paper discusses the damage mechanisms such as sigma phase embrittlement, stress relaxation cracking and creep.

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Friction Stir Welding – An Advanced Approach To Repair Nuclear Power Plant Components

Product Number: ED22-17314-SG

Author: W.Tang, M.Gussev, X.Chen, T.M Rosseel

Publication Date: 2022

$20.00

The harsh environment such as elevated temperature, radiation, elevated pressure, and potentially corrosive in nuclear reactors compromises material performance. Over time, repair and/or replacement through welding is needed for damaged parts and components. Thus, repair welding is essential to ensure the long-term viability, competitiveness, and safe lifetime extensions of the existing US reactor fleet.

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Important Factors in Pipe Butt Welding of Super Duplex Stainless Steel (SDSS) UNS S32760 Using the GTAW Welding Process

Product Number: MPWT19-14287

Author: Dr. Glenn Byrne

Publication Date: 2019

$0.00

The paper considers best practice to realise the optimum combination of strength, toughness,
corrosion resistance and radiographic integrity in UNS S32760 pipe girth welds made using the
GTAW process.
Aspects of fit up, tacking, root gap are considered. The effect of weld heat input and heat input
control through the thickness of the joint, welding technique, inter pass temperature control and
the use of different combinations of shielding and backing gasses on corrosion resistance of
joints is presented. Current specification, procedure and welder qualification requirements are
discussed, as is the need for supplementary testing, in particular quantitative microstructural
evaluation.

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Metallurgical and Micostructural Effect on CVN Impact Toughness in 2,25Cr1Mo Weld Metal

Product Number: MPWT19-15280

Author: Bertoni Dott, Markus Gustafson, Eva-Lena Bergquist

Publication Date: 2019

$0.00

2,25 Cr 1 Mo steel is required to comply with very stringent technical requirements when such a steel is applied in the Refinery Industry.Most of the attention is focused on the impact toughness performance of the weld metal which provides information on the structural stability of the pressure vessel taking into account the defect’s growth resistance in the welded joint.The assessment of welded joint toughness by performing CVN tests as a measure of this resistance remains the simplest and most widespread. Bainitic microstructure with very low ferrite content and small grain size of the primary austenite are effective in improving the CVN impact toughness at low temperature after min and max PWHT. The aforementioned microstructure is promoted by lowering the temperature of the Bs in addition to the heat input. Carbide precipitation at grain boundaries doesn’t significantly affect the impact properties of the weld metal after the industrial min and max PWHTs. The micro slag inclusions are investigated. Their chemical composition, volume and size is limited in the weld metal and they do not affect the CVN weld metal property. Min PWHT and max PWHT transform the Martensite/Austenite microstructure developed in the weld metal in as welded condition to Bainitic microstructure and the size and distribution of the carbide precipitated into the matrix. The PWHTs do not modify significantly the grain size of the microstructure which is mainly managed by chemistry and heat input. The type of current DC+ and AC significantly affect the chemistry of the weld metal providing different content of C, Mn, Si, Oxygen. Their contributions enhance the CVN impact properties especially when AC is used

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Microstructure Characterization Of Additively Manufactured Alloy 718

Product Number: 51323-19419-SG

Author: Liu Cao, Dian Li, Sydney Fields, Yufeng Zheng

Publication Date: 2023

$20.00

Alloy UNS N07718 (hereafter abbreviated as 718) is one of the most versatile precipitation-hardened nickel-based corrosion-resistant alloys (CRAs) used for both surface and sub-sea components in oil and gas production service. API 6ACRA provides heat treatment windows and acceptance criteria for 718 in these oil and gas production environments, in which the heat treatment is intended to homogenize the microstructure and obtain the correct microstructure for targeting the desired mechanical properties. For fabricating high temperature materials via additive manufacturing (AM), alloy 718 is a primary focus due to its widespread applications in the past 60 years and excellent weldability in either age hardened or annealed condition.

Products tagged with 'microstructure'

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