Microstructure and phase composition of diffusion coating formed in NiCr alloys by hot-dip aluminizing

The article examines the technology of nitro-oxidation, which consists of nitriding in separated ammonia at the first organize and oxidation in water vapor at the second stage of the process, studied the structure and phase composition of the diffusion nitride-oxide layer, providing high physico-mechanical and physicochemical surface characteristics, competitively capable of galvanic strategies of getting a coating, the conceivable outcomes of regulating the structure and phase composition of the nitride-oxide layer are being investigated to obtain a diffusion coating composition with predetermined properties.

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Formation of the Diffusion Zone in Explosion Welded Composite Cr20Ni80 - AD1 at Liquid-Phase Interaction

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.410.531 ◽

2021 ◽

Vol 410 ◽

pp. 531-536

Author(s):

Victor Georgievich Shmorgun ◽

Artem I. Bogdanov ◽

Dmitriy V. Shcherbin

Keyword(s):

Heat Treatment ◽

Phase Composition ◽

Liquid Phase ◽

Ternary Compound ◽

Diffusion Zone ◽

Diffusion Coating ◽

Phase Interaction ◽

Coating Structure

The paper presents the investigation on the structure, chemical and phase composition of the diffusion coating formed during the liquid-phase heat treatment in the explosion-welded Cr20Ni80 + AD1 bimetal. It is shown that the coating structure consists of NiAl3, CrAl7, Ni2Al3 intermetallic inclusions, as well as a metastable ternary compound – τ2-phase (Al77.5Cr12.5Ni10) of different dispersion and morphology. There are no crystallization defects in the coating structure.

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The Effects of Aluminum Activity on Aluminide Coating Formation of Nickel-Base Superalloy

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.198-199.32 ◽

2012 ◽

Vol 198-199 ◽

pp. 32-35

Author(s):

Feng Zhou ◽

Ming Gao ◽

Ying Che Ma ◽

Gan Feng Tu ◽

Ke Wu Peng

Keyword(s):

Phase Composition ◽

Aluminide Coating ◽

Diffusion Coating ◽

Pack Cementation ◽

Nickel Base Superalloy ◽

Aluminum Activity ◽

Coating Formation ◽

Al Powder ◽

Nickel Base ◽

Base Superalloy

The effects of different pure Al compositon in the pack powder on aluminide coating formation of a new kind of Ni-Cr-W-Al nickel-base superalloy by pack cementation aluminizing was investigated. The content of pure Al powder is 15% and 30% in the aluminizing agent. The microstructure and phase composition of diffusion coating was studied.

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FORMATION OF THE STRUCTURE AND COMPOSITION OF THE DIFFUSION INTERACTION ZONE DURING THE HEAT TREATMENT OF THE EXPLOSION-WELDED AD1 + Cr20Ni80 COMPOSITE IN THE PRESENCE OF A LIQUID PHASE

IZVESTIA VOLGOGRAD STATE TECHNICAL UNIVERSITY ◽

10.35211/1990-5297-2021-2-249-7-11 ◽

2021 ◽

pp. 7-11

Author(s):

V. G. Shmorgun ◽

A. I. Bogdanov ◽

D. V. Shcherbin ◽

V. P. Kulevich

Keyword(s):

Heat Treatment ◽

Phase Composition ◽

Melting Point ◽

Liquid Phase ◽

Intermetallic Compounds ◽

Diffusion Coating ◽

Phase Interaction ◽

Interaction Zone ◽

Coating Structure ◽

Study Results

The paper presents the study results of the structure, chemical and phase composition of the diffusion coating formed during the heat treatment of the explosion-welded Cr20Ni80 + AD1 bimetal according to the regime providing liquid-phase interaction (above the melting point of aluminum) on the surface of the Cr20Ni80 alloy. It is shown that its structure consists of inclusions of NiAl, CrAl, NiAl intermetallic compounds, as well as a metastable ternary compound - τ-phase with composition of AlCrNi of different dispersion and morphology. There are no crystallization defects in the coating structure.

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