Analysis of the precipitation process of the intermetallic phases in a high-temperature Fe–Ni austenitic alloy

2003 ◽  
Vol 81 (2-3) ◽  
pp. 490-492 ◽  
Author(s):  
K.J. Ducki ◽  
M. Hetmańczyk ◽  
D. Kuc
Keyword(s):  
High Temperature ◽  
Intermetallic Phases ◽  
Precipitation Process ◽  
Austenitic Alloy

PARALLOY H39WM

Alloy Digest ◽  
1995 ◽  
Vol 44 (5) ◽  
Keyword(s):  
High Temperature ◽  
Physical Properties ◽  
Tensile Properties ◽  
Austenitic Alloy ◽  
Temperature Performance

Abstract PARALLOY H39WM is an austenitic alloy developed for severe service in furnace coils up to 1135 C (2075 F). This datasheet provides information on composition, physical properties, and tensile properties. It also includes information on high temperature performance as well as casting and joining. Filing Code: SS-594. Producer or source: Paralloy Ltd.

scholarly journals The Influence of La and Ce on Microstructure and Mechanical Properties of an Al-Si-Cu-Mg-Fe Alloy at High Temperature

Metals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 384
Author(s):  
Andong Du ◽  
Anders E. W. Jarfors ◽  
Jinchuan Zheng ◽  
Kaikun Wang ◽  
Gegang Yu
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
High Temperature ◽  
Intermetallic Phases ◽  
High Temperature Strength ◽  
Thermal Expansion Mismatch ◽  
Strengthening Mechanisms ◽  
High Temperature Mechanical Properties ◽  
Minor Contribution ◽  
A Minor

The effect of lanthanum (La)+cerium (Ce) addition on the high-temperature strength of an aluminum (Al)–silicon (Si)–copper (Cu)–magnesium (Mg)–iron (Fe)–manganese (Mn) alloy was investigated. A great number of plate-like intermetallics, Al11(Ce, La)3- and blocky α-Al15(Fe, Mn)3Si2-precipitates, were observed. The results showed that the high-temperature mechanical properties depended strongly on the amount and morphology of the intermetallic phases formed. The precipitated tiny Al11(Ce, La)3 and α-Al15(Fe, Mn)3Si2 both contributed to the high-temperature mechanical properties, especially at 300 °C and 400 °C. The formation of coarse plate-like Al11(Ce, La)3, at the highest (Ce-La) additions, reduced the mechanical properties at (≤300) ℃ and improved the properties at 400 ℃. Analysis of the strengthening mechanisms revealed that the load-bearing mechanism was the main contributing mechanism with no contribution from thermal-expansion mismatch effects. Strain hardening had a minor contribution to the tensile strength at high-temperature.

TEM and X-Ray Examinations of Intermetallic Phases and Carbides Precipitation in an Fe-Ni Superalloy during Prolonged Ageing

2013 ◽  
Vol 212 ◽  
pp. 15-20
Author(s):  
Kazimierz J. Ducki ◽  
Jacek Mendala ◽  
Lilianna Wojtynek
Keyword(s):  
Heat Treatment ◽  
Solution Heat Treatment ◽  
Intermetallic Phase ◽  
Intermetallic Phases ◽  
Precipitation Process ◽  
Secondary Phases ◽  
X Ray Diffraction ◽  
Solid Samples ◽  
Structural Investigations ◽  
X Ray

The influence of prolonged ageing on the precipitation process of the secondary phases in an Fe-Ni superalloy of A-286 type has been studied. The samples were subjected to a solution heat treatment at 980°C for 2 h and water quenched, and then aged at temperatures of 715, 750 and 780°C at holding times from 0.5 to 500 h. Structural investigations were conducted using TEM and X-ray diffraction methods. The X-ray phase analyses performed on the isolates were obtained by anodic dissolution of the solid samples. After solution heat treatment the alloy has the structure of twinned austenite with a small amount of undissolved precipitates, such as carbide TiC, carbonitride TiC0.3N0.7, nitride TiN0.3, carbosulfide Ti4C2S2, Laves phase Ni2Si, and boride MoB. The application of ageing causes precipitation processes of γ-Ni3(Al,Ti), G (Ni16Ti6Si7), η (Ni3Ti), β (NiTi) and σ (Cr0.46Mo0.40Si0.14) intermetallic phases, as well as the carbide M23C6. It was found that the main phase precipitating during alloy ageing was the γ intermetallic phase.

Magnesium intermetallics: synthesis and structure of Eu2Pt2Mg and Sr2Pt2Mg

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Maximilian Kai Reimann ◽  
Rainer Pöttgen
Keyword(s):  
High Temperature ◽  
Chemical Bonding ◽  
Valence Electron ◽  
Intermetallic Phases ◽  
Type Structure

Abstract The intermetallic phases Sr2Pt2Mg and Eu2Pt2Mg were obtained by reaction of the elements in sealed tantalum tubes at high temperature. Sr2Pt2Mg crystallizes with the monoclinic Ca2Ir2Si type (C2/c, a = 1020.7(7), b = 597.7(4), c = 827.0(4) pm, β = 103.37(5)°), while Eu2Pt2Mg adopts the orthorhombic W2CoB2-type structure (Immm, a = 440.31(5), b = 582.20(6), c = 914.11(9) pm, wR = 0.0359, 277 F 2 values, 14 variables). The magnesium atoms in both structures are coordinated by four Pt2 dumb-bells with a rectangular planar coordination in Eu2Pt2Mg (268 pm Pt–Mg) and a distorted tetrahedral one in Sr2Pt2Mg (273–275 pm Pt–Mg). The Pt–Pt distances are 277 pm in the europium and 269 pm in the strontium compound. The polyanionic [Pt2Mg] units are planar in Eu2Pt2Mg and separated by the europium atoms. The Sr2Pt2Mg structure shows the motif of hexagonal rod packing for the [Pt2Mg] rows that are embedded in a strontium matrix. Chemical bonding and the influence of the valence electron count on the formation of the structure types are discussed.

scholarly journals A Review on the High Temperature Strengthening Mechanisms of High Entropy Superalloys (HESA)

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5835
Author(s):  
Malefane Joele ◽  
Wallace Rwisayi Matizamhuka
Keyword(s):  
High Temperature ◽  
Configurational Entropy ◽  
Extended Period ◽  
Theoretical Models ◽  
Intermetallic Phases ◽  
Processing Route ◽  
Strengthening Mechanisms ◽  
High Entropy ◽  
Use Of Resources ◽  
The Impact

The studies following HEA inceptions were apparently motivated to search for single-phase solid solution over intermetallic phases, accordingly made possible by the concept of high configurational entropy. However, it was realised that the formation of intermetallic phases in HEAs is prevalent due to other criterions that determine stable phases. Nonetheless, recent efforts have been directed towards attributes of microstructural combinations. In this viewpoint, the techniques used to predict microstructural features and methods of microstructural characterisation are elucidated in HESA fields. The study further analyses shortcomings regarding the design approaches of HESAs. A brief history is given into how HESAs were developed since their birth, to emphasize the evaluation techniques used to elucidate high temperature properties of HESAs, and the incentive thereof that enabled further pursuit of HESAs in the direction of optimal microstructure and composition. The theoretical models of strengthening mechanisms in HEAs are explained. The impact of processing route on the HESAs performance is analysed from previous studies. Thereafter, the future of HESAs in the market is conveyed from scientific opinion. Previous designs of HEAs/HESAs were more based on evaluation experiments, which lead to an extended period of research and considerable use of resources; currently, more effort is directed towards computational and theoretical methods to accelerate the exploration of huge HEA composition space.

Weldability of the MSRB Magnesium Alloy

2011 ◽  
Vol 176 ◽  
pp. 107-118 ◽  
Author(s):  
Janusz Adamiec
Keyword(s):  
Solid Solution ◽  
High Temperature ◽  
Magnesium Alloy ◽  
Intermetallic Phases ◽  
Structural Constituent ◽  
Temperature Range ◽  
Partial Tears ◽  
Recovery Temperature

This work, in combination with industrial tests of casting welding, shows that the causes of high-temperature brittleness are the partial tears of the structure and the hot cracks of both the castings, as well as the welded and padded joints. Such phenomena should be treated as irreversible failures caused by the process of crystallization that is in the area of co-existence of the solid and liquid structural constituent. Nil-strength temperature (NST), nil-ductility temperature (NDT) and ductility recovery temperature (DRT) were determined using Gleeble 3800. Obtained results enabled the defining of brittle temperature range of MSR-B magnesium alloy. The assessment of the resistance to hot fractures was conducted on the basis of the transvarestriant trial. The transvarestriant trial involves changing of strain during welding. It was stated that the range of the high-temperature brittleness is very broad, which significantly limits the application of the welding techniques to join or repair elements made of the MSRB alloy. brittleness is caused mainly by metallurgical factors, i.e. precipitation of intermetallic phases from the solid solution.

The Effect of Alloy Addition on the High Temperature Properties of Over-Aged Al-Si(CuNiMg) Cast Alloys

2006 ◽  
Vol 519-521 ◽  
pp. 461-466 ◽  
Author(s):  
Young Hee Cho ◽  
Dae Heon Joo ◽  
Chul Hyun Kim ◽  
Hu Chul Lee
Keyword(s):  
High Temperature ◽  
Elevated Temperature ◽  
Volume Fraction ◽  
Metastable Phase ◽  
Intermetallic Phases ◽  
Alloying Elements ◽  
High Temperature Strength ◽  
Transition Elements ◽  
Cast Alloys ◽  
Equilibrium Phases

The role of alloying elements in the improvement of the high temperature strength of Al-12Si(CuNiMg) cast alloys used for automotive piston applications was investigated. The addition of alloying elements such as Mn, Cr, Ti and Ge was studied and the detailed characterization of the composition and morphology of the constituent phases after over aging at 350 for 1000 hrs was performed. The compositions and volume fractions of the equilibrium phases determined by thermodynamic calculation were compared with the experimental results. The addition of transition elements, including Mn, Cr and Ti, increased the volume fraction of the intermetallic phases, which effectively enhanced the high temperature strength of the alloys. Among these transition elements, Mn turned out to be the most effective alloying element. After adding up to 0.5wt% of Mn, a large number of intermetallic phases, α-Al(Mn,Fe)Si as well as fine Al6(Mn,Fe) particles were precipitated and a significant improvement in the elevated temperature properties was achieved. The addition of Ge promoted the precipitation of the θphase (metastable phase, θ-Al2Cu), due to the formation of GeSi precipitates, thereby improved the mechanical properties of the alloy after T6 heat treatment. However, the presence of these GeSi precipitates did not affect the coarsening of the θ phase to form Qphase( Al5Cu2Mg8Si6) during aging and, thus, the elevated temperature properties were not improved by the addition of Ge.

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