Menu
Search
Filters
Close
Menu

Celebrate World Corrosion Awareness Day with 20% off eCourses and eBooks with code WCAD2024 at checkout!

51318-11233-Cyclic Oxidation Behavior of Ni-Cr Alloys in Wet Air

Picture for Cyclic Oxidation Behavior of Ni-Cr Alloys in Wet Air
Available for download

Both commercial and model Ni-based alloys were tested in 1-h cycles at 800-950°C in wet air, and the oxide scales formed on wrought Ni-(14-25)wt%Cr binary alloys were characterized.

Product Number: 51318-11233-SG
Author: Jiheon Jun / Dongwon Shin / Sebastien Dryepondt, / J. Allen Haynes / Bruce A. Pint
Publication Date: 2018
Industry: Science of Corrosion
$0.00
$20.00
$20.00

For automotive exhaust valve applications, future vehicles will need affordable, durable materials capable of operating at higher temperatures with predictable response to severe oxidizing environments. Both commercial and model Ni-based alloys were tested in 1-h cycles at 800-950°C in wet air, and the oxide scales formed on wrought Ni-(14-25)wt%Cr binary alloys were characterized to gain a better understanding of the behavior of chromia-forming alloys under these conditions. The mass change curves were used to quantify the behavior of the tested alloys and fit growth and spallation rates using the kp-p model. We systematically analyzed the correlation between elemental alloy compositions and the manually fitted kp and p values to select high-ranking features to be included in a machine learning analysis. The machine learning models for the rate, kp, could be trained with a surprisingly high accuracy even with limited data, while only modest fitting was obtained for p, the spallation parameter. A preliminary theoretical framework that can predict kp and p of hypothetical alloys was established, however, improving the accuracy of surrogate models is needed to assist in alloy development for this transportation application.

Key words: Ni alloy, chromia scales, cyclic oxidation, exhaust valve, mass change modeling, correlation analysis, machine learning

For automotive exhaust valve applications, future vehicles will need affordable, durable materials capable of operating at higher temperatures with predictable response to severe oxidizing environments. Both commercial and model Ni-based alloys were tested in 1-h cycles at 800-950°C in wet air, and the oxide scales formed on wrought Ni-(14-25)wt%Cr binary alloys were characterized to gain a better understanding of the behavior of chromia-forming alloys under these conditions. The mass change curves were used to quantify the behavior of the tested alloys and fit growth and spallation rates using the kp-p model. We systematically analyzed the correlation between elemental alloy compositions and the manually fitted kp and p values to select high-ranking features to be included in a machine learning analysis. The machine learning models for the rate, kp, could be trained with a surprisingly high accuracy even with limited data, while only modest fitting was obtained for p, the spallation parameter. A preliminary theoretical framework that can predict kp and p of hypothetical alloys was established, however, improving the accuracy of surrogate models is needed to assist in alloy development for this transportation application.

Key words: Ni alloy, chromia scales, cyclic oxidation, exhaust valve, mass change modeling, correlation analysis, machine learning

Product tags
Also Purchased
Picture for Applicability of ASTM G28 testing
Available for download

51318-11243-Applicability of ASTM G28 testing

Product Number: 51318-11243-SG
Author: Briony Holmes / Kasra Sotoudeh
Publication Date: 2018
$20.00

There appears to be a need for long-term service data for wrought and welded materials with grain boundary precipitation, which can then be compared with ASTM G28 or ASTM A262 data to provide confidence in utilizing such materials.
Picture for Abrasive Blasted Surface Preparation – Does the Pipeline Coating Industry Really Understand it?
Available for download

51318-11245-Abrasive Blasted Surface Preparation – Does the Pipeline Coating Industry Really Understand it?

Product Number: 51318-11245-SG
Author: Shiwei William Guan
Publication Date: 2018
$20.00

Three recent international pipeline projects illustrate that the typical surface profile height and abrasive blast cleaning requirements in today’s coating standards and specifications have not been sufficient to define the adequate level of the abrasive blasting.
Picture for 51318-11232- Mechanism of CO2 Corrosion of Mild Steel: a New Narrative
Available for download

51318-11232- Mechanism of CO2 Corrosion of Mild Steel: a New Narrative

Product Number: 51318-11232-SG
Author: Aria Kahyarian, Bruce Brown, and Srdjan Nesic
Publication Date: 2018
$20.00

The increased corrosion rates of mild steel in acidic solutions in the presence of CO2, previously associated with carbonic acid direct reduction, are in fact due to the increased rate of iron dissolution in the presence of CO2
Categories
Industry
Recently viewed
Popular tags
View all

Association for Materials Protection and Performance

© AMPP All Rights Reserved.
Membership Terms of Content Use
Contact Customer Support