scholarly journals Characteristics of the Evolution of Carbide Morphology in the Haynes® 230® Alloy as a Result of High Temperature Annealing

2021 ◽  
Vol 60 (4) ◽  
pp. 109-119
Author(s):  
Małgorzata Warmuzek ◽  
Adelajda Polkowska ◽  
Tomasz Paweł Dudziak
Keyword(s):  
Microstructure Evolution ◽  
Morphological Evolution ◽  
Phase Evolution ◽  
Chemical Compositions ◽  
Matrix Interface ◽  
High Temperature Annealing ◽  
Secondary Carbides ◽  
Carbide Morphology ◽  
Carbide Matrix ◽  
Carbide Particles

In this work, results of an investigation of the microstructure evolution in Haynes® 230® alloy are presented. The morphological and chemical compositions of the chosen microstructure’s constituents, such as the primary and secondary carbides, were analyzed based on tests in the temperature range 700–800 °C for 1000–3000 h. The prediction of phase evolution within the microstructure was proposed based on the analysis of mutual replacement of carbide-forming elements at the carbide/matrix interface. Based on the results, some complementary markers were considered to describe Haynes® 230® microstructure evolution. Qualitative markers, i.e., defined morphological features, were related to the shape and distribution of microstructure constituents. The study also used quantitative markers related to the local chemical compositions of carbide particles, determined as the ratio of the concentrations of carbide-forming elements Crc/Wc, Crc/CrM and Wc/WM. Microstructure maps created on the basis of these complementary markers for the successive annealing stages reflected the course of its morphological evolution.

The use of high-resolution methods of research in the design of the diamond-matrix interface to increase the durability of the diamond tool

2020 ◽  
Vol 86 (6) ◽  
pp. 62-71
Author(s):  
P. P. Sharin ◽  
S. P. Yakovleva ◽  
M. P. Akimova ◽  
V. I. Popov
Keyword(s):  
High Resolution ◽  
Diamond Tool ◽  
Diamond Surface ◽  
Matrix Interface ◽  
Reaction Products ◽  
Diamond Tools ◽  
Functional Composites ◽  
Mechanical Adhesion ◽  
Carbide Matrix ◽  
Diamond Retention

The results of studying fundamental and applied problems regarding the formation of boundary layers between diamond and carbide matrix are presented with the goal to develop a highly resistant diamond tool. The new approaches to the synthesis of diamond-carbide materials combining diamond metallization and sintering in a single-stage technology are presented. The developed technology eliminates the re-heating of a metallized coatings which results in their destruction and enhanced graphitization of diamond (these phenomena restrict using metallization procedure to improve diamond retention and synthesis of high-functional composites for diamond tools). The goal of the study is analysis the structural and phase state of the «diamond – carbide matrix» interface in a diamond tool obtained by the new technology and the main factors determining the level of diamond retention in the presence of a metallized coating. Unique opportunities provided by modern high-resolution methods of research were used in the study. The elemental composition and morphological features of the diamond-matrix interface were studied using the methods of scanning electron microscopy, atomic force microscopy, X-ray microanalysis and Raman spectroscopy. Identification of the reaction products, including non-diamond carbon was performed. It is shown that the introduction of the powder-metallizer significantly modified the contact boundaries and provide conditions for improving the chemical and mechanical adhesion of the diamond-matrix system. The formation of the well-developed nano- and sub-microscale roughness of the diamond surface and dense filling of the existing voids with nanoscale layers of metal-infiltrate was revealed. The multilevel organization of highly structured elements of the transition zone with the minimal graphitization ensured the monolithic character and strength of the diamond-matrix bond. Comparative service tests of preproduction and control samples of diamond dressers proved the efficiency of developed hybrid technology (the specific performance of diamond tools increased by 39 – 45%). New fundamental and applied results have been obtained in the field of studying interface zones in crystalline multiphase systems that can be used to regulate adhesion phenomena at the interphase boundaries and develop highly efficient composite materials.

Microstructure evolution of a ZrC coating layer in TRISO particles during high-temperature annealing

2016 ◽  
Vol 479 ◽  
pp. 93-99 ◽  
Author(s):  
Daejong Kim ◽  
Young Bum Chun ◽  
Myeong Jin Ko ◽  
Hyeon-Geun Lee ◽  
Moon-Sung Cho ◽  
...  
Keyword(s):  
High Temperature ◽  
Microstructure Evolution ◽  
Coating Layer ◽  
High Temperature Annealing ◽  
Triso Particles ◽  
Zrc Coating

Microstructure Evolution of Undercooled Austenite during Deformation for Medium-Carbon Si-Mn Steel

2011 ◽  
Vol 704-705 ◽  
pp. 903-906
Author(s):  
Yun Li Feng ◽  
Shao Qiang Yuan ◽  
Meng Song
Keyword(s):  
Microstructure Evolution ◽  
Ferrite Matrix ◽  
Eutectoid Reaction ◽  
Deformation Bands ◽  
Degree Of Deformation ◽  
Medium Carbon ◽  
Transmission Electron ◽  
Mn Steel ◽  
Carbide Particles ◽  
Undercooled Austenite

The microstructure evolution of a medium-carbon Si-Mn steel during deformation of undercooled austenite at different degree of deformation, temperatures and strain rates has been investigated by means of a hot compression simulation test, metallographic microscope, scanning electron microscope and transmission electron microscopy. Also, the mechanism of carbide spheroidized during deformed process has been discussed. The experiment results demonstrate that the process of evolution experienced three stages: that is, strain-induced transformation, austenite eutectoid decomposed to carbides and ferrite matrix, and spheroidization of pearlite at the range of A3-Ar3. The austenitic grains would be refined for the extra-product of ferrite above the Ar3. The eutectoid reaction was induced on the grain boundaries of ferrite and non-transformed austenite and deformation bands with the increasing volume of deformation. An optimum combination of deformation temperature and strain rate is important to obtian the dulplex microstructure consisting of ultrafine ferrites and dispersed carbide particles. The fine spheroidized microstructures are obtained while the deformed temperature reaches 650°C with ≥1.0, meanwhile, The carbides precipate in globular and shot-rod shapes. Keywords: Medium-carbon Si-Mn steel, Undercooled austentite, Microstructure evolution, Deformation induced transformation, Carbide spheroidization

scholarly journals Phase evolution, characterisation, and performance of cement prepared in an oxy-fuel atmosphere

2016 ◽  
Vol 192 ◽  
pp. 113-124 ◽  
Author(s):  
Liya Zheng ◽  
Thomas P. Hills ◽  
Paul Fennell
Keyword(s):  
Particle Size ◽  
Compressive Strength ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Carbon Capture ◽  
Raw Materials ◽  
Carbon Capture And Storage ◽  
Phase Evolution ◽  
Chemical Compositions ◽  
Phase And Elemental Compositions

Cement manufacture is one of the major contributors (7–10%) to global anthropogenic CO2 emissions. Carbon capture and storage (CCS) has been identified as a vital technology for decarbonising the sector. Oxy-fuel combustion, involving burning fuel in a mixture of recycled CO2 and pure O2 instead of air, makes CO2 capture much easier. Since it combines a theoretically lower energy penalty with an increase in production, it is attractive as a CCS technology in cement plants. However, it is necessary to demonstrate that changes in the clinkering atmosphere do not reduce the quality of the clinker produced. Clinkers were successfully produced in an oxy-fuel atmosphere using only pure oxides as raw materials as well as a mixture of oxides and clay. Then, CEM I cements were prepared by the addition of 5 wt% gypsum to the clinkers. Quantitative XRD and XRF were used to obtain the phase and elemental compositions of the clinkers. The particle size distribution and compressive strength of the cements at 3, 7, 14, and 28 days' ages were tested, and the effect of the particle size distribution on the compressive strength was investigated. Additionally, the compressive strength of the cements produced in oxy-fuel atmospheres was compared with those of the cement produced in air and commercially available CEMEX CEM I. The results show that good-quality cement can be successfully produced in an oxy-fuel atmosphere and it has similar phase and chemical compositions to CEM I. Additionally, it has a comparable compressive strength to the cement produced in air and to commercially available CEMEX CEM I.

Influence of High Temperature Annealing on Microstructure Evolution of Ni-24Fe-14Cr-8Mo Superalloy

2021 ◽  
Vol 904 ◽  
pp. 117-123
Author(s):  
Yi Cui ◽  
Yun Fei Zhang ◽  
Yan Guang Han ◽  
Da Lv
Keyword(s):  
High Temperature ◽  
Microstructure Evolution ◽  
Testing Machine ◽  
Aging Treatment ◽  
Growth Patterns ◽  
High Temperature Annealing ◽  
Rockwell Hardness ◽  
Hardness Testing ◽  
X Ray Diffraction ◽  
X Ray

The effect of high temperature annealing on microstructure evolution of Ni-24Fe-14Cr-8Mo alloy was investigated through Optical Microscopy (OM), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD) and Rockwell Hardness Testing Machine. Three kinds of grain growth patterns were found at different annealing temperatures due to carbides precipitation and dissolution. After a combination of high temperature annealing and aging treatment, the hardness versus time curves performed a parabolic pattern. The highest hardness was achieved under 1070°C/60 minutes treatment, and the desirable annealing time should be 60 minutes to 90 minutes.

Study on CPM9V High Speed Steel Ring Prepared by Spray Forming

2011 ◽  
Vol 311-313 ◽  
pp. 624-630
Author(s):  
Yi Xu ◽  
Chang Chun Ge
Keyword(s):  
High Speed ◽  
Technological Parameter ◽  
Preparation Method ◽  
High Speed Steel ◽  
Alloy Element ◽  
Spray Forming ◽  
Regular Shape ◽  
Carbide Morphology ◽  
Carbide Particles ◽  
Deposition Substrate

CPM9V high speed steel(HSS) ring billet was prepared by spray forming(SF), the yield is 83.5%, porosity is 0.8%, spray forming preparation method and technological parameter were illustrated. The microstructure and carbide morphology on the different position of billet were observed. The results show that carbide particles have small size, regular shape and uniform distribution, alloy element without segregation. There are some pores and defects in the position of ring billet closed to deposition substrate, come from spray forming instability beginning stage.

PHASE EVOLUTION AND MAGNETIC PROPERTIES OF FEPT-PTTE2 NANORODS

2009 ◽  
Vol 23 (17) ◽  
pp. 3573-3578
Author(s):  
QINGYU YAN ◽  
AIDONG LI
Keyword(s):  
Magnetic Properties ◽  
Phase Transformation ◽  
High Temperature ◽  
Annealing Temperature ◽  
Phase Evolution ◽  
Polyol Process ◽  
Phase Ratio ◽  
High Temperature Annealing ◽  
Two Phase

FePt - PtTe 2 two phase nanorods have been produced by a polyol process. The shape and magnetic properties of two phase nanorods with different phase ratio are investigated. L10 phase transformation of FePt in the nanorods has been accomplished at annealing temperature as low as 400 °C with Hc above 500mT. High temperature annealing causes the disintegration of the nanorods due the melting/evaporation of Te element.

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