Evaluation of Microstructures of Hot-Rolled Mg-La-Zr Alloys

The development of new low-cost alloys composed of common elements that show high biocompatibility and mechanical properties matching with human bone is the target of many researches recently. Design and controlling the mechanical properties of newly developed set of Ti-xFe-3Zr-yNb (x=3-8 & y=2-3, at.%) low-cost alloys through applying different thermomechanical treatments is the aim of this work. Fe-content in the present designed alloys is changing in the range 3 to 8 at.%. The hardness and Young's modulus of the alloys were measured for the alloys in the solution treated, hot rolled and subsequent ageing at 400 °C and 550 °C. The phases separation and hence hardness of the aged alloys at 400 °C and 550 °C are highly dependent on the Fe-content in the alloy. The Young's modulus of the alloys is also changing with the Fe-content and heat treatment, where lowest modulus (~80GPa) is shown in the Ti-5Fe-3Zr-3Nb alloy in the solution treated condition.

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Effect of rolling on the fractional recrystallization behaviour of Al-Mg and Al-Mg-Zr alloys

Journal of Mechanical Engineering ◽

10.3329/jme.v48i1.41091 ◽

2019 ◽

Vol 48 (1) ◽

pp. 24-29

Author(s):

M. S. Kaiser ◽

K. M. Shorowordi ◽

H. M. Mamun Al Rashed

Keyword(s):

Mg Alloy ◽

Micro Hardness ◽

Type Analysis ◽

Annealing Temperatures ◽

Hardness Variation ◽

High Annealing ◽

Cold Rolled ◽

Hot Rolled ◽

Zr Alloy ◽

Zr Alloys

One set of Al–Mg and Al-Mg-Zr alloys are directly cold rolled and other set of those alloys are hot rolled and then cold rolled using a laboratory rolling mill. The effect of rolling on the fractional recrystallization of the alloys has been investigated using the micro-hardness variation. Isothermally annealed samples are also studied using JMAK type analysis to see if there exists any correlation between experimental and JMAK type analysis. From the microstructure, it is observed that the Al-Mg alloy becomes almost fully recrystallized state after annealing at 600°K for 60 minutes. The results also show that recrystallization fraction obtained by the two methods, shows the higher variation in zirconium added Al-Mg alloy as compared to the Al-Mg alloy. The fractional recrystallization of the cold rolled Al-Mg-Zr alloy is significantly lower than that of cold rolled Al-Mg alloy and hot and colled rolled Al-Mg-Zr, owing to the presence of fine Al3Zr precipitates. These metastable L12 Al3Zr precipitates are thermally stable at high annealing temperatures.

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Microstructure and mechanical properties of hot-rolled Mg–Zn–Nd–Zr alloys

Materials Science and Engineering A ◽

10.1016/j.msea.2006.09.149 ◽

2008 ◽

Vol 483-484 ◽

pp. 228-230 ◽

Cited By ~ 26

Author(s):

Wenjiang Ding ◽

Daquan Li ◽

Qudong Wang ◽

Qiang Li

Keyword(s):

Mechanical Properties ◽

Microstructure And Mechanical Properties ◽

Hot Rolled ◽

Zr Alloys

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Precipitation in Al-Li-Zr alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100121338 ◽

1992 ◽

Vol 50 (1) ◽

pp. 186-187

Author(s):

D.M. Vanderwalker

Keyword(s):

Fracture Toughness ◽

Precipitation Hardening ◽

Weight Ratio ◽

High Strength ◽

Transmission Electron ◽

Water Quench ◽

Aluminum Lithium ◽

Aluminum Lithium Alloys ◽

Lithium Alloys ◽

Zr Alloys

Aluminum-lithium alloys have a low density and high strength to weight ratio. They are being developed for the aerospace industry.The high strength of Al-Li can be attributed to precipitation hardening. Unfortunately when aged, Al-Li aquires a low ductility and fracture toughness. The precipitate in Al-Li is part of a sequence SSSS → Al3Li → AlLi A description of the phases may be found in reference 1 . This paper is primarily concerned with the Al3Li phase. The addition of Zr to Al-Li is being explored to find the optimum in properties. Zirconium improves fracture toughness and inhibits recrystallization. This study is a comparision between two Al-Li-Zr alloys differing in Zr concentration.Al-2.99Li-0.17Zr(alloy A) and Al-2.99Li-0.67Zr (alloy B) were solutionized for one hour at 500oc followed by a water quench. The specimens were then aged at 150°C for 16 or 40 hours. The foils were punched into 3mm discs. The specimens were electropolished with a 1/3 nitric acid 2/3 methanol solution. The transmission electron microscopy was conducted on the JEM 200CX microscope.

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Observations on the structure at the transformation interface of pearlite in steel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100174138 ◽

1990 ◽

Vol 48 (4) ◽

pp. 200-201

Author(s):

F. A. Khalid ◽

D. V. Edmonds

Keyword(s):

Room Temperature ◽

Thin Foil ◽

Carbon Steels ◽

Model Alloy ◽

Growth Interface ◽

Medium Carbon ◽

Solution Treated ◽

Medium Carbon Steels ◽

Alloy Carbide ◽

Hot Rolled

The austenite/pearlite growth interface in a model alloy steel (Fe-1 lMn-0.8C nominal wt%) is being investigated. In this particular alloy pearlite nodules can be grown isothermally in austenite that remains stable at room temperature, thus facilitating examination of the transformation interfaces. This study presents preliminary results of thin foil TEM of the austenite/pearlite interface, as part of a programme of aimed at studying alloy carbide precipitation reactions at this interface which can result in significant strengthening of microalloyed low- and medium- carbon steels L Similar studies of interface structure, made on a partially decomposed high- Mn austenitic alloy, have been reported recently.The experimental alloys were made as 50 g argon arc melts using high purity materials and homogenised. Samples were hot- rolled, swaged and machined to 3mm diameter rod, solution treated at 1300 °C for 1 hr and WQ. Specimens were then solutionised between 1250 °C and 1000 °C and isothermally transformed between 610 °C and 550 °C for 10-18 hr and WQ.

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THE STRUCTURE OF AMORPHOUS Ni-Zr ALLOYS

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1985825 ◽

1985 ◽

Vol 46 (C8) ◽

pp. C8-181-C8-185

Author(s):

A. E. Lee ◽

S. Jost ◽

Ch. N.J. Wagner ◽

L. E. Tanner

Keyword(s):

Zr Alloys

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Development of trimming technology for hot rolled ultra-low carbon steel

Revue de Métallurgie ◽

10.1051/metal/199390070917 ◽

1993 ◽

Vol 90 (7-8) ◽

pp. 917-922

Author(s):

Y. Matsuda ◽

M. Nishino ◽

J. Ikeda

Keyword(s):

Carbon Steel ◽

Low Carbon Steel ◽

Low Carbon ◽

Ultra Low Carbon Steel ◽

Hot Rolled

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Investigation on the control of multiphase flow behavior in a continuous casting tundish during ladle change

Metallurgical Research & Technology ◽

10.1051/metal/2020070 ◽

2020 ◽

Vol 117 (6) ◽

pp. 619

Author(s):

Rui Xu ◽

Haitao Ling ◽

Haijun Wang ◽

Lizhong Chang ◽

Shengtao Qiu

Keyword(s):

Multiphase Flow ◽

Flow Behavior ◽

Rolled Strip ◽

Impact Zone ◽

Steel Cleanliness ◽

Carry Over ◽

Slag Carry Over ◽

Hot Rolled ◽

Turbulence Inhibitor ◽

The Impact

The transient multiphase flow behavior in a single-strand tundish during ladle change was studied using physical modeling. The water and silicon oil were employed to simulate the liquid steel and slag. The effect of the turbulence inhibitor on the slag entrainment and the steel exposure during ladle change were evaluated and discussed. The effect of the slag carry-over on the water-oil-air flow was also analyzed. For the original tundish, the top oil phase in the impact zone was continuously dragged into the tundish bath and opened during ladle change, forming an emulsification phenomenon. By decreasing the liquid velocities in the upper part of the impact zone, the turbulence inhibitor decreased considerably the amount of entrained slag and the steel exposure during ladle change, thereby eliminating the emulsification phenomenon. Furthermore, the use of the TI-2 effectively lowered the effect of the slag carry-over on the steel cleanliness by controlling the movement of slag droplets. The results from industrial trials indicated that the application of the TI-2 reduced considerably the number of linear inclusions caused by ladle change in hot-rolled strip coils.

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