Research Progress on Improving the High-Temperature Oxidation Resistance of MCrAlY Coatings

2015 ◽  
Vol 52 (12) ◽  
pp. 120004
Author(s):  
周圣丰 Zhou Shengfeng ◽  
刘佳 Liu Jia ◽  
熊征 Xiong Zheng ◽  
戴晓琴 Dai Xiaoqin ◽  
李玲华 Li Linghua ◽  
...  
Keyword(s):  
High Temperature ◽  
Oxidation Resistance ◽  
High Temperature Oxidation ◽  
Research Progress ◽  
Temperature Oxidation ◽  
Mcraly Coatings

Microstructure Characteristics and High-Temperature Oxidation Behavior of Plasma-Sprayed and Laser-Remelted MCrAlY Coatings on TiAl Intermetallics

2011 ◽  
Author(s):  
Zongjun Tian ◽  
Lida Shen ◽  
Zhidong Liu ◽  
Yinhui Huang
Keyword(s):  
High Temperature ◽  
Oxidation Resistance ◽  
Plasma Spraying ◽  
High Temperature Oxidation ◽  
Intermetallic Alloys ◽  
Laser Remelting ◽  
Temperature Oxidation ◽  
Mcraly Coatings ◽  
Tial Intermetallics ◽  
Plasma Sprayed

In order to further improve the high-temperature oxidation resistance of TiAl intermetallic alloys, MCrAlY coatings were fabricated by plasma spraying and plasma spraying-laser remelting technologies. The microstructures of the as-sprayed and laser-remelted MCrAlY coatings were studied. In addition, the oxidation behaviors at 850 °C for three samples were investigated. One sample is the matrix of TiA1 intermetallic alloys, the other one is processed by plasma-spraying MCrAlY coatings, and the third one is processed by plasma-spraying and laser-remelting MCrAlY coatings. It was revealed that the oxidation resistance of TiAl intermetallics is weak due to lack of protection of Al2O3 film formed on the surface. The plasma-sprayed MCrAlY coatings have better oxidation resistance than the TiAl intermetallics although the plasma-sprayed MCrAlY coatings have high density of porosity and a typical layered structure. It is demonstrated that most of the holes can be eliminated by laser remelting, leading to the best oxidation resistance of the third sample with the laser-remelted coatings. The high oxidation resistance of the laser-remelted coatings is mainly attributed to three aspects: firstly, an Al enriched zone on the coating surface is formed during laser remelting, which is transformed into a protective Al2O3 film during oxidation process. Secondly, laser remelting eliminates most of the defects in plasma-sprayed coatings and enhances its density, thus decreases the channel of oxidation diffusion in high temperature oxidation process. Thirdly, rapid cooling of laser remelting results in a grain refinement and a preferred oxidation of Al at the initial stage, leading to a reduction of oxidation rate.

AK STEEL 441

Alloy Digest ◽  
2006 ◽  
Vol 55 (6) ◽  
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
High Temperature ◽  
Tensile Properties ◽  
Oxidation Resistance ◽  
Ferritic Stainless Steel ◽  
High Temperature Oxidation ◽  
High Temperature Strength ◽  
Temperature Oxidation ◽  
Temperature Performance

Abstract AK Steel 441 has good high-temperature strength, an equiaxed microstructure, and good high-temperature oxidation resistance. The alloy is a niobium-bearing ferritic stainless steel. This datasheet provides information on composition, hardness, and tensile properties as well as deformation. It also includes information on high temperature performance and corrosion resistance as well as forming and joining. Filing Code: SS-965. Producer or source: AK Steel.

Sign in / Sign up

Export Citation Format

Share Document