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Experimental Investigation and Numerical Simulation of the Grain Size Evolution during Isothermal Forging of a TC6 Alloy
Miaoquan LI,Shankun XUE,Aiming XIONG,Shenghui CHEN,
Miaoquan LI
,Shankun XUE,Aiming XIONG and Shenghui CHEN State Key Laboratory of Solidification Processing,School of Materials Science and Engineering,Northwestern Polytechnical University,Xi''''an,China

材料科学技术学报 , 2005,
Abstract: Hot compression was conducted at a Thermecmaster-Z simulator, at deformation temperatures of 800~1040℃, with strain rates of 0.001~50 s-1 and height reduction of 50%. Grain size of the prior α phase was measured with a Leica LABOR-LUX12MFS/ST microscope to which QUANTIMET 500 software for image analysis for quantitative metallography was linked. According to the present experimental data, a constitutive relationship for a TC6 alloy and a model for grain size of the prior α phase were established based on the Arrhenius' equation and the Yada's equation,respectively. By finite element (FE) simulation, deformation distribution was determined for isothermal forging of a TC6 aerofoil blade at temperatures of 860~940℃ and hammer velocities of 9~3000.0 mm/min. Meanwhile, the grain size of the prior α phase is simulated during isothermal forging of the TC6 aerofoil blade, by combining FE outputs with the present grain size model. The present results illustrate the grain size and its distribution in the prior α phase during the isothermal forging of the TC6 aerofoil blade. The simulated results show that the height reduction, deformation temperature, and hammer velocity have significant effects on distribution of the equivalent strain and the grain size of the prior α phase.
PRECIPITATION OF TiC IN METASTABLE β-Ti ALLOY
YU Xuejie WANG Jianlin Shanghai Iron and Steel Research Institute,Shanghai,ChinaZHOU Tianjian Anhui Institute of Technology,Hefei,China YU Xuejie,Senior Engineer,Shanghai Iron Steel Research Institute,Taihe Road,Wusong,Shanghai,China.
金属学报(英文版) , 1989,
Abstract: In order to clarify that the IFP and the “Type 2”α phase are also arising from TiC,ametastable β-Ti alloy was selected for investigation in this work.The results showed that af-ter heating the alloy just below the α+β→β transus temperature and quenching,the TiC lay-er existed at the α/β interface.The morphology of TiC is similar to that of the IFP arisingfrom TiH_2 in the α-β two-phase alloys.The IFP TiC also provided an easy crack path orthe crack initiation sites.The fracture is also identical to that caused by IFP TiH_2.The arceddiffractions(characteristic of “Type 2”α)were found in the selected area diffraction pat-terns of some specimens which had been isothermally aged after solid solution treatment.Theparticles which bring on the arced diffractions may be TiC on the basis of structure and lat-tice parameter analysis,not the so called “Type 2”α phase.
Microstructure evaluation of the Al-Ti alloy with magnesium addition  [PDF]
K. Labisz,L.A. Dobrzański,R. Maniara,A. Olsen
Journal of Achievements in Materials and Manufacturing Engineering , 2011,
Abstract: Purpose: Effects of magnesium additions to Al alloy with 2% Ti addition on the microstructure, phase morphology and distribution and mechanical properties were investigated. Here are presented mainly microstructure changes after solution heat treatment concerning mainly grain uniformity and intermetallic phases of the aluminium – titanium alloy with a content of 2 and 4 % of magnesium addition. The purpose of this work was also to determine the solution heat treatment conditions of the investigation alloys.Design/methodology/approach: The reason of this work was to determine the heat treatment parameters influence, particularly SHT temperature and time onto the changes of the microstructure of the investigated material, as well to determine which intermetallic phases occur after the heat treatment performed, and how is the particles morphology in as cast state compared to structure after heat treatment.Findings: After solution heat treatment for 4 hours the structure changes in a significant way. The grains are larger and no more uniform as in the as cast state. The most stable intermetallic in the Al-Ti system is the Al3Ti phase. The solution heat treatment time should be greater than 4 hours to ensure a proper solution of titanium and magnesium in the Al-α solid solution.Research limitations/implications: The investigated aluminium samples were examined metallographically using optical microscope with different image techniques, scanning electron microscope and also analyzed using a Vickers micro-hardness tester, also EDS microanalysis was carried out.Practical implications: As an implication for the practice an alloy can be developed with increased properties, which could be of great interest for the automotive or aerospace industry. There are existing many different investigation areas and the knowledge found in this research shows one of interesting investigation direction.Originality/value: The combination of light weight and high strength achieved in the Al-Ti alloys is very attractive for aerospace and automotive industries. Addition of magnesium into the Al-Ti alloy could help also to reveal the existence new unknown phases.
Microstructure and mechanical properties of the Al-Ti alloy with calcium addition  [PDF]
L.A. Dobrzański,K. Labisz,A. Olsen
Journal of Achievements in Materials and Manufacturing Engineering , 2008,
Abstract: Purpose: In this paper there are presented the investigation results of mechanical properties and microstructure with intermetallic phases of the aluminium – titanium alloy with a defined content of Ca addition. The purpose of this work was also to determine the heat treatment conditions for solution heat treatment of the investigation alloys.Design/methodology/approach: The reason of this work was to determine the heat treatment influence, particularly solution heat treatment time to the changes of the microstructure, as well to determine which intermetallic phases occur after the heat treatment performed, and how is the morphology of these particles.Findings: After solution heat treatment for 4 hours the structure changes in a way, that the grains are larger and no more uniform as showed before. The most stable intermetallic in the Al-Ti system is the Al3Ti phase. The solution heat treatment time should be greater than 4 hours to ensure a proper solution of titanium and calcium in the Al-α solid solution.Research limitations/implications: The investigated aluminium samples were examined metallographically using optical microscope with different image techniques, SEM, TEM and analyzed using a Vickers micro-hardness tester, also EDS microanalysis was made.Practical implications: As an implication for the practice a new alloy can be developed, some other investigation should be performed in the future, but the knowledge found in this research shows an interesting investigation direction.Originality/value: The combination of light weight and high strength Ti-based alloys is very attractive for aerospace and automotive industries. Furthermore, the presence of calcium can bring into existence new unknown phases as well can enhance the thermal stability of ternary Al-Ti-Ca alloy because of its higher melting point then Al-Ti.
Microstructure and mechanical properties of the Al-Ti alloy with cerium addition  [PDF]
L.A. Dobrzański,K. Labisz,R. Maniara,A. Olsen
Journal of Achievements in Materials and Manufacturing Engineering , 2009,
Abstract: Purpose: In this work there are presented the investigation results of mechanical properties and microstructure concerning mainly intermetallic phases of the aluminium – titanium alloy with a defined content of 2 and 4 % of cerium addition. The purpose of this work was also to determine the heat treatment conditions for solution heat treatment of the investigation alloys.Design/methodology/approach: The reason of this work was to determine the heat treatment influence, particularly solution heat treatment time to the changes of the microstructure, as well to determine which intermetallic phases occur after the heat treatment performed, and how is the morphology of these particles.Findings: After solution heat treatment for 4 hours the structure changes. The grains are larger and no more uniform as showed before. The most stable intermetallic in the Al-Ti system is the Al3Ti phase. The solution heat treatment time should be greater than 4 hours to ensure a proper solution of titanium and cerium in the Al-α solid solution.Research limitations/implications: The investigated aluminium samples were examined metallographically using optical microscope with different image techniques, scanning electron microscope and also analyzed using a Vickers micro-hardness tester, also EDS microanalysis was made.Practical implications: As an implication for the practice a new alloy can be developed, some other investigation should be performed in the future, but the knowledge found in this research shows an interesting investigation direction.Originality/value: The combination of light weight and high strength Ti-based alloys is very attractive for aerospace and automotive industries. Furthermore, the presence of calcium cerium into existence new unknown phases as well can enhance the thermal stability of ternary Al-Ti-Ce alloy because of its higher melting point then Al-Ti.
STUDY ON Ti Ni La HYDROGEN STORAGE ALLOY
DM Zhang,ZYFu State Key Lab of Advanced Technology for Materials Synthesisand Processing,Wuhan University of Technology,Wuhan,China,
D.M. Zhang and Z.Y.Fu State Key Lab of Advanced Technology for Materials Synthesisand Processing
,Wuhan University of Technology,Wuhan,China

金属学报(英文版) , 1999,
Abstract: In ordertoimprovethe dischargecapacity of Ti2 Ni hydrogen storage alloy, the phases and effecton the property for Ti Nialloy with alittle La( La contentisbetween 5 25 wt% and12 62 wt%) were investigated in this paper. It is found that La exists in the form ofLaNi5 ,thesecond phase,in Ti Nialloy when La> 8 wt% . LaNi5 phasecaneffectivelyim provethe activity property and discharge capacity of Ti Ni alloy. While the soluble Ti inmain phase Ti2 Niisadverseto hydrogen adsorption desorption cycle and itshould be dimin ished .
Thermal Conductivity of Cu-Cr-Zr-Ti Alloy in the Temperature Range of 300–873?K  [PDF]
S. Chenna Krishna,N. Supriya,Abhay K. Jha,Bhanu Pant,S. C. Sharma,Koshy M. George
ISRN Metallurgy , 2012, DOI: 10.5402/2012/580659
Abstract: In the present investigation, thermal conductivity of Cu-Cr-Zr-Ti alloy was determined as the product of the specific heat ( ), thermal diffusivity ( ), and density ( ) in the temperature range of 300–873?K. The experimental results showed that the thermal conductivity of the alloy increased with increase in temperature up to 873?K and the data was accurately modeled by a linear equation. For comparison, thermal conductivity was also evaluated for OFHC copper in the same temperature range. The results obtained were discussed using electrical conductivity and hardness measurements made at room temperature. Transmission electron microscopy (TEM) was done to understand the microstructural changes occurring in the sample after the test. Wiedemann-Franz-Lorenz law was employed for calculating electronic and phonon thermal conductivity using electrical conductivity. On the basis of studies conducted it was deduced that in situ aging may be one of the reasons for the increase in thermal conductivity with temperature for Cu-Cr-Zr-Ti alloy. 1. Introduction Cu-Cr-Zr alloy is a candidate material for high heat flux applications like the inner wall of a thrust chamber and the first wall of nuclear reactor owing to its high conductivity and strength [1, 2]. The high conductivity of the alloy is attributed to the low solubility of Cr and Zr in copper at room temperature [3], while the strength is due to the precipitation of Cr and Cu5Zr in copper matrix [4, 5]. Zirconium plays an additional role of fixing elemental sulphur and suppresses dynamic embrittlement [6]. The alloy used in the present study is modified by the addition of titanium of Cu-Cr-Zr alloy. Titanium plays a role similar to that of zirconium in Cu-Cr-Zr alloy in suppressing dynamic embrittlement by fixing elemental sulphur as titanium sulphide [7]. Limited literature is available on mechanical properties, microstructure and thermal properties of Cu-Cr-Zr-Ti alloy. Lack of thermal conductivity data for the alloy at elevated temperature promoted us to design experiments to evaluate the same in the temperature of 300–873?K. 2. Experimental Procedure Hot rolled and annealed plate of Cu-0.61Cr-0.038Zr-0.029Ti-0.003Fe (wt%) alloy was used in the present study. Small pieces cut from the plate were used for hardness, thermal, and electrical conductivity measurement. In addition, properties of OFHC copper (C10100) were evaluated in the annealed condition. OFHC copper represents the pure form of copper, and the effect of alloying elements (Cu-Cr-Zr-Ti) can be better understood by comparison. Thermal
Mechanism of Burn Resistance of Alloy Ti40

Yongqing ZHAO,Lian ZHOU,Kangying ZHU,Henglei QU,Huan WU,

材料科学技术学报 , 2001,
Abstract: The Ti fire found in high performance engines promotes the development of burn resistant Ti alloys. The burn resistant mechanism of Ti40 alloy is investigated. Ti40 alloy reveals good burn resistance. Its interfacial products between burning products and the matrix are tenacious, which retard the diffusion of oxygen into the matrix. Two burn resistant mechanisms, that is, fast scatter dispersion of heat and suppression of oxygen diffusion, are proposed.
Ti CONTENT AND STRUCTURE OF ELECTRODEPOSITED AI-Ti ALLOY POWDER
电沉积Al—Ti合金粉的含Ti量及其结构

GUO Jiaju,WEI Zhenqiang,
过家驹
,魏振强,郭乃名

腐蚀科学与防护技术 , 2000,
Abstract: The effects of electdeposited wndition on chemical canposition of deposited Al-Ti alloy paYder were studied in Im temperature mlten salts (below 200°C ). ?he relationship between chemical amposition and structure were examined by X-ray diffraction and ?EM electmn diffraction. 'The results indicated that when Ti content of deposited Al-Ti alloy &er was less than 23 % , the alloy pa~der was solid solution of Ti in Al, when Ti content was 44 % , the alloy &er becane Am intemtallic canpound.
ON THE STEADY STATE CREEP OF ALLOY Ti-679

Cao Mingzhou,Zhao Jixiang,Su Ge,Wan Xiaojing,

金属学报 , 1981,
Abstract: The steady state creep rate of alloy Ti-679 under various temperatures and stresses was examined. A cyclic test on strain rate was also made of its apparent activated area as a function of temperature. Some approaches to the creep mechanism of the alloy are discussed.
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