Microstructure Evolution of AlSn20Cu Alloy Prepared by Conventional Casting and Semi Continuous Casting during Rolling and Annealing

2021 ◽  
Vol 904 ◽  
pp. 31-38
Author(s):  
Shu Hui Huang ◽  
Bao Hong Zhu ◽  
Yong An Zhang ◽  
Hong Wei Liu ◽  
Sheng Li Guo
Keyword(s):  
Grain Size ◽  
Continuous Casting ◽  
Area Fraction ◽  
Temperature Deformation ◽  
Casting Method ◽  
Important Indicator ◽  
Average Grain Size ◽  
Deformation Amount ◽  
Bearing Materials ◽  
Better Than

AlSn20Cu alloy is currently one of the most widely used bearing materials, and its microstructure is the most important indicator in application. In this paper, AlSn20Cu alloy ingots were prepared by two methods: ordinary casting and semi-continuous casting, and deformation and annealing process of the two ingots were studied. Scanning electron microscope (SEM) and Image Pro Plus software were used to observe and analyze the evolution of the microstructure, and the morphological information such as the average grain size and area fraction of the Sn phase was quantitatively characterized. The effects of casting method, deformation temperature, deformation amount and annealing temperature on the morphology of Sn phase were studied in this paper. Compared with ordinary casting, the cooling rate of semi-continuous casting is higher, so the Sn phase is smaller, the casting defects are less, and the deformability of the alloy is better. The AlSn20Cu alloy prepared by ordinary casting has better deformability at about 140 °C, while the AlSn20Cu alloy prepared by semi-continuous casting can be rolled and deformed at room temperature. When the deformation is greater than 40%, after annealing at 250 °C, the average grain size of the Sn phase in the AlSn20Cu alloy prepared by semi-continuous casting is around one hundred square microns and the area fraction is more than 10%, and the Sn phase morphology is better than ordinary casting alloy under any processing conditions.

A High Effective and Low-Cost Modifier for Hypereutectic Al-Si Alloys

2013 ◽  
Vol 721 ◽  
pp. 282-286
Author(s):  
Guang Hui Qi
Keyword(s):  
Grain Size ◽  
Master Alloy ◽  
Low Cost ◽  
Environment Pollution ◽  
Casting Method ◽  
Good Future ◽  
Primary Si ◽  
Average Grain Size ◽  
Master Alloys

In order to settle environment pollution and provide a high effective and low-cost modifier for refining the primary Si in hypereutectic Al-Si alloys, Al-Fe-P master alloys containing 2.0~5.0% phosphorus have been invented by casting method. The Al-Fe-P master alloys can be conveniently produced and an excellent modification can be obtained by adding 0.3~0.8wt% Al-Fe-P master alloy in Al-Si alloys containing 12%-25% Si at a relatively lower modifying temperature. The number of primary Si increases obviously and the average grain size of primary Si decreases largely, less than 50μm. Furthermore Al-Fe-P master alloys have many advantages, such as low cost, convenient operation technology, no pollution, stable and long-term modification effect, easy storage and etc. Al-Fe-P master alloys have overcome the shortages of current modifier and have a good future for hypereutectic Al-Si alloy modification.

Preparation and Characterization of As-Cast and Hot-Rolled Mg-5Al-0.3Mn-1Ce Alloy

2011 ◽  
Vol 284-286 ◽  
pp. 1559-1563 ◽  
Author(s):  
Jian Li Wang ◽  
Jian Ping Li ◽  
Li Min Wang ◽  
Li Dong Wang
Keyword(s):  
Grain Size ◽  
Test Results ◽  
Casting Method ◽  
Rolled Sample ◽  
Cast Sample ◽  
Average Grain Size ◽  
Dislocation Strengthening ◽  
Hot Rolled ◽  
Mould Casting

Mg-5Al-0.3Mn-1Ce alloy was prepared by metal mould casting method. The as-cast ingot was homogenized and hot-rolled with total thickness reduction of 61% after four passes. Texture, microstructure and mechanical properties of the studied alloy were investigated. Results showed that the as-cast sample was mainly composed of a-Mg, Mg17Al12and Al11Ce3phases. Average grain size of the as-cast sample was about 500 μm. After hot-rolling, average grain size was greatly refined to about 20 μm. Further more, the long acicular Al11Ce3phase was smashed to small pieces. Tensile test results demonstrated that ultimate tensile strength and yield strength of the hot-rolled sample were improved by 65.2% and 165% respectively compared with those of the as-cast sample. Strength enhancement was attributed to grain refining strengthening and dislocation strengthening mechanisms.

scholarly journals Comparison of the Microstructure of M2 Steel Fabricated by Continuous Casting and with a Sand Mould

Metals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 560
Author(s):  
Jinwen Zhang ◽  
Zhigang Zhao ◽  
Wenxian Wang ◽  
Yutian Wang
Keyword(s):  
Grain Size ◽  
Continuous Casting ◽  
Cooling Rate ◽  
Continuous Caster ◽  
Casting Process ◽  
Sand Mold ◽  
Average Grain Size ◽  
Kg Medium ◽  
The Relationship ◽  
Continuous Casting Billet

AISI M2 steel was smelted in a 150 kg medium-frequency induction furnace and cast to form round billets with a cross-section diameter of 100 mm via a vertical continuous caster and sand mold. The secondary dendrite arm spacing (λ2), cooling rates, permeability and size and distribution of grains and network carbides of the two billets were studied. The results show that the continuous casting process can effectively decrease the λ2 value, permeability and size of the grains and carbides and improve the distribution of the grains and carbides during solidification. The λ2 values of the billets cast with a sand mold and continuous caster are 37.34 μm and 21.14 μm, respectively, and the cooling rate is 3.6 K·s−1 and 12.0 K·s−1, respectively. The area fractions of carbides at the center of the billets cast with the sand mold and continuous caster are 0.24 and 0.16, respectively, and increase by 27.7% and 25.4%, respectively, compared with their average values. The average grain size of billets cast with the sand mold and continuous caster is 69.4 μm and 50.5 μm, respectively. Compared with the sand mold billet, the grain size at the center of the continuous casting billet is reduced by 25.5%. The relationship between the grain size and cooling rate is presented in this paper.

Microstructure of Al2O3-Fe FGM Obtained by Modified Slip-Casting Method

2005 ◽  
Vol 492-493 ◽  
pp. 665-672 ◽  
Author(s):  
A. Ozieblo ◽  
Tomasz Wejrzanowski ◽  
K. Konopka ◽  
Mikolaj Szafran ◽  
Krzysztof Jan Kurzydlowski
Keyword(s):  
Magnetic Field ◽  
Grain Size ◽  
Magnetic Force ◽  
Volume Fraction ◽  
Slip Casting ◽  
Functionally Graded ◽  
Casting Method ◽  
Average Grain Size ◽  
Field Lines ◽  
The Magnetic Field

This paper describes the technology and microstructure of Al2O3-Fe functionally graded composites, FGM, obtained by slip-casting under magnetic field. Alumina a-Al2O3, provided by Alcoa (symbol A16SG), with average grain size of 0.5 µm, and iron powder, (symbol Distaloy AB) from Hoganas, with average grain size of 35 µm, were used to produce a series of specimens which differed in contents of Fe particles in Al2O3. As a source of magnetic force a permanent magnet was used. Preforms were sintered in a vacuum at temp. 1470oC. The microstructures of the specimens were quantitatively described via stereological methods. Sections, parallel to the magnetic field lines were analyzed using special image analysis software. Stereological methods presented in this work have been used to determine gradient in the volume fraction of the Fe particles and variation in their size and dispersion. These parameters are essential for controlling the technological process of interest and to design microstructure for needed properties (fracture toughness).

Compression and Compressive Creep Behaviors in Titanium Aluminides Alloyed with Vanadium comprizing Gamma + Beta Dual Phase Microstructures

2006 ◽  
Vol 980 ◽  
Author(s):  
Tohru Takahashi ◽  
Yohji Kojima ◽  
Koshiro Otsuka
Keyword(s):  
Grain Size ◽  
Stress Exponent ◽  
Room Temperature ◽  
Vanadium Content ◽  
Ternary Alloys ◽  
Temperature Deformation ◽  
Dual Phase ◽  
Proof Stress ◽  
Compressive Creep ◽  
Average Grain Size

AbstractFine grained gamma+beta dual phase microstructures were obtained in aluminum-titanium-vanadium ternary alloys containing 40 at.% aluminum and 60 at.% (titanium and vanadium). Average grain size was about 5, 3, and 2 micrometers in the recrystallized materials containing 20, 30, and 40 at.% vanadium, and the phase constitution was around 50vol.% gamma phase and 50vol.% beta phase. Compression behavior was investigated at temperatures ranging from the room temperature up to 1200K, and compressive creep tests were carried out at 1050-1200K in order to characterize the temperature and chemical composition dependences of strength and deformation. These gamma+beta microduplex materials showed very high strength at room temperature; 0.2% proof stress was around 1200MPa. The compression deformability decreased from about 0.2 to 0.05 true strain with increasing vanadium content. The grain size effect was not clarified yet, but it was rather disappointing that smaller-grained material with Al40Ti20V40 composition did not show effective improvement either in strength or in deformability. 0.2% proof stress showed a considerable weakening at temperatures higher than 900K; the onset temperature of softening became lower as the vanadium content increased. In Al40Ti40V20 material with about 5 micrometer grains, both gamma and beta grains were flattened up to 1000K, however, above 1100K the gamma grain showed no significant shape change even after a heavy deformation. This is probably because the gamma grains were relatively stronger than the beta grains. The gamma grains showed tendency toward agglomeration, which is similar to rafting of precipitate particles. Surface relief was observed after high temperature deformation suggesting activity of boundary sliding on grain boundaries and interfaces. Compressive creep behavior was investigated under a constant true stress in vacuum. Creep curves consisted of a small amount of normal primary transient, the minimum creep rate region, and a steady or slightly accelerating creep region. Stress exponent decreased to about 2 with decreasing vanadium content. It was rather unexpected that smaller grained Al40Ti20V40 material showed larger stress exponent around 3.

Comparative Study on Microstructure and Texture of Ti-IF Steel Sheets Produced by Different Hot Rolling Processing

2011 ◽  
Vol 418-420 ◽  
pp. 726-730
Author(s):  
Yun Li Feng ◽  
Ming Cai ◽  
Li Bin Chen
Keyword(s):  
Grain Size ◽  
Hot Rolling ◽  
Diffraction Method ◽  
Rolling Process ◽  
X Ray Diffraction ◽  
Steel Sheets ◽  
Size Number ◽  
Average Grain Size ◽  
Metallographic Observation ◽  
Better Than

It was analyzed by metallographic observation and X-ray diffraction method that the microstructure and texture in two kinds of Ti-IF steels, which produced by different hot rolling process,and it also was discussed that the formability and the texture in Ti-IF steels. The results showed that the microstructures of these two kinds of steels are Equiaxed ferrite grains, but the grain sizes are greatly different. Respectively the average grain size of steel A and B are 24.85μm and 11.85μm, and the average grain size number are 7.4 and 9.5. The {111} texture of steel B is stronger than A, besides, the deep drawing properties of steel B is better than A in the reason that disadvantaged texture{001} and {112} are not founded in steel B.

scholarly journals On the digitalization of the parameters of native gold particles in the study of placers and concentrate and mineralogical studies

2021 ◽  
pp. 60-72
Author(s):  
BARANNIKOV Aleksandr Grigor’evich ◽  
Keyword(s):  
Grain Size ◽  
Native Gold ◽  
Digital Data ◽  
Grain Size Analysis ◽  
Size Analysis ◽  
Important Indicator ◽  
Gold Particles ◽  
Rigorous Approach ◽  
Average Grain Size ◽  
Average Size

Relevance of the work is due to the need to increase the efficiency of studying the particles of native gold in placers using morphometric (morphogranulometric) parameters in their documentation. Graphic materials (maps, plans, sections) based on digitalization of the collected data help to increase the reliability of the forecast, make it possible to use the selected areolas in combination with other methods when assessing ore-bearing zones and areas. Purpose of the work: development of a systematics of native gold identification on a morphometric basis. Substantiation on the basis of digital data of placer samples indicators – form of gold grains, average grain size, hydraulic particle size; study of the spatial variability of the revealed parameters of the metal within the rebuilt placers. Research methodology: diagnostics (description) of the morphology of gold grains and other typomorphic features based on the quantitative parameters of particles with the subsequent calculation of the shape coefficients (flatness, elongation); generalization and interpretation of the results of the description of native gold previously obtained during the exploration of the Ural placers. Results. The proposed systematics of native gold outwards on a morphometric basis allows a more rigorous approach to the identification of metal particles (excluding the subjectivity of describing the outward look of ore). When substantiating the average size of gold grains, significant discrepancies were noted in the results obtained by two independent methods: when measuring the parameters of gold grains on a morphogranulometric basis and using traditional sieve grain size analysis. The geological factors that determine the level of discrepancy between the compared methods are considered. It is about how the revealed discrepancies should be taken into account in the practice of forecasting and prospecting works. It is argued that the most important indicator characterizing the migratory mobility of gold particles in an aquatic environment is their hydraulic size (HS, cm/s). An approach to substantiating HS based on measurements of morphogranulometric parameters of particles (axes A, B, C) is proposed. Examples are considered based on the interpretation of the accumulated digital data in the mineralogical mapping of a number of ore-bearing areas and sites. Conclusions. Long years of studying native gold from placers using the developed systematics of particles on a digital (morphogranulometric) basis have been tested by the practice of forecasting and prospecting and research works. The described approach, based on digitalization of the accumulated information, is recommended for implementation and further improvement

Effect of Al5Ti1B Master Alloy on Microstructure and Mechanical Properties of Al-5wt.%Cu based Alloy

2014 ◽  
Vol 1051 ◽  
pp. 195-198 ◽  
Author(s):  
Ming Yu Xie ◽  
Si Hai Ao ◽  
Xiang Wang
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Master Alloy ◽  
Heterogeneous Nucleation ◽  
Aging Treatment ◽  
Casting Method ◽  
Nucleation Sites ◽  
Average Grain Size ◽  
Addition Level ◽  
Different Levels

The Al-5wt.%Cu based alloy with different levels of Al5Ti1B master alloy additions have been prepared by conventional casting method. The effect of Al5Ti1B contents on microstructure of Al-Cu based alloy was studied by means of XRD, OM and SEM. The results show that when the addition level of Al5Ti1B master alloy is less than 0.6wt.%, the average grain size of the alloys decreases with the increase of Al5Ti1B content. But the grain size increases somewhat with further addition of Al5Ti1B. It is considered that TiB2 particles can serve as the heterogeneous nucleation sites of α-Al during solidification, and heterogeneous nucleation is the main reason of the grain refinement of Al-Cu based alloy. The superior comprehensive mechanical properties of tensile strength of 435 MPa and elongation of 11% of the refined Al-5wt.%Cu based alloy with 0.6% Al5Ti1B were obtained after solution and aging treatment.

Comparative Study on Microstructure of Pb(Mg1/3Nb2/3)O3-PbTiO3 Ceramics

2005 ◽  
Vol 475-479 ◽  
pp. 1201-1204
Author(s):  
Chun Hong Li ◽  
Qiang Li ◽  
Feng Bing Song
Keyword(s):  
Grain Size ◽  
Comparative Study ◽  
Phase Boundary ◽  
Morphotropic Phase Boundary ◽  
Precursor Method ◽  
Average Grain Size ◽  
Columbite Precursor ◽  
Better Than

(1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 ((1-x)PMN-xPT, PMN-PT) with composition near the morphotropic phase boundary (MPB) were prepared by the columbite precursor method and the rutile precursor method respectively. Attention has been focused on the influence of process on microstructure of PMN-PT ceramics. The results show that the average grain size of ceramics is insensitive to composition for both above processes. The refinement and homogeneity on grain size in the rutile precursor method is better than that in the columbite precursor method.

Numerical Simulation of Hot Forging for the Disc of Superalloy GH4169

2011 ◽  
Vol 328-330 ◽  
pp. 1598-1601
Author(s):  
Yan Shu Zhang ◽  
Xiao Fei Liu
Keyword(s):  
Grain Size ◽  
Strain Rate ◽  
Volume Fraction ◽  
Hot Forging ◽  
Pure Titanium ◽  
Constant Strain Rate ◽  
High Temperature Deformation ◽  
Temperature Deformation ◽  
Stress Strain ◽  
Average Grain Size

In this paper, the hot deformation behavior of GH4169 superalloy were investigated at temperature of 900-1020°C and at strain rate of 0.001-0.1up to a 60% height reduction of the sample using isothermal constant strain rate compression tests on process annealed material. The high temperature deformation behaviour of pure titanium was characterized based on an analysis of the stress–strain curves The proposed constitutive equation and the stress-strain curves were implanted into DEFORM2D, a hot forging process for the disc of GH4169 was simulated, and the micro-variable, recrystallized volume fraction, average grain size, recrystallized grain size and etc., were plotted with a contoured figure. According to the comparision between the experimental and predicted result, the absolute error between them is acceptable. The method for microstructure prediction will be significant to the engineering.

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