Project No: FE0007332
Performer: Tennessee Technological University


Contacts

Richard A. Dennis
Technology Manager, Turbines
National Energy Technology Laboratory
3610 Collins Ferry Road
P.O. Box 880
Morgantown, WV 26507-0880
304-285-4515
richard.dennis@netl.doe.gov

Patcharin Burke
Project Manager
National Energy Technology Laboratory
626 Cochrans Mill Road
P.O. Box 10940
Pittsburgh, PA 15236-0940
412-386-7378
patcharin.burke@netl.doe.gov

Ying Zhang
Principal Investigator
Tennessee Technological University
TTU Box 5014, 115 W. 10th Street
Cookeville, TN 38505-0001
931-372-3265
yzhang@tntech.edu

Duration
Award Date:  09/12/2011
Project Date:  09/11/2015

Cost
DOE Share: $371,288.00
Performer Share: $95,227.00
Total Award Value: $466,515.00

Performer website: Tennessee Technological University - http://www.tntech.edu

Advanced Energy Systems - Hydrogen Turbines

An Alternative Low-Cost Process for Deposition of McRally Bond Coats for Advanced Syngas/Hydrogen Turbine Applications

Project Description

The proposed metal chromium-aluminum-yttrium (MCrAlY; where M = nickel [Ni], cobalt [Co] or a mixture of Ni and Co) bond coats will be synthesized via an electrolytic codeposition process, followed by a post-plating heat treatment. In contrast to traditional electro-codeposition processes where sulfate or sulfamate bath is used for Ni/Co deposition, a sulfur-free electrolyte will be employed to control the impurity levels in the MCrAlY coatings. The reduced sulfur (S) levels will be expected to improve oxide scale adhesion. The amounts of Cr, Al, and particularly the Y reservoir, in the MCrAlY bond coat will be optimized to extend the lifetime of the thermal barrier coating (TBC) system. Reactive elements such as Y + hafnium (Hf) or Y + zirconium (Zr) will be co-doped into the MCrAlY coatings by modifying the composition of the CrAlY alloy powder. The composition of the CrAlY+ alloy (where "+" equals Hf or Zr, etc.) will be carefully designed, based on the literature data for model MCrAlY alloys and other types of MCrAlY coatings. Other parameters of the electrolytic codeposition process will be systematically studied using a design-of-experiment approach to provide a fundamental understanding of their synergistic effects and to optimize the coating composition and microstructure.

 

Laboratory electro-codeposition process.


Program Background and Project Benefits

This project will utilize a novel coating process to synthesize a nickel/cobalt- chromium-aluminum-yttrium (MCrAlY) bond coat. Turbine materials research seeks to improve coating materials that will allow for higher temperature operation and increased durability leading to increased turbine efficiency and reduced maintenance. Specifically, this project will use electro-codeposition to deposit optimally designed MCrAlY bond coats using a sulfur free electrolyte and analyze the process and resulting bond coats for effects on composition and microstructure.


Accomplishments