G0401-1-4 Evaluation of performance in compression test of high strength magnesium alloys

This paper deals with friction properties and deformation resistance during hot forming of Mg-Al-Ca-Mn series magnesium alloys. Friction coefficients between dies and magnesium alloys were obtained by ring compression tests that used graphite, PTFE, and an oil lubricant in a hot-forging process. Hot forging was performed under various conditions to clarify the effects of types of lubricants and slide motion of the press machines on friction properties. Two types of slide motion, a constant velocity motion and a pulse motion were selected in the ring-compression test. It was found that graphite with an oil lubricant effectively eliminated die sticking in hot forming of magnesium alloys. The isothermal deformation resistances were derived using friction coefficients obtained by ring-compression tests as well as finite-element simulations. The predicted stress strain curves with temperature were examined with the stress-strain relationship obtained in experiments using a servo press and demonstrated the effectiveness of the proposed method.

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Development of High Strength, High-Strain-Rate Superplastic Magnesium Alloys.

Journal of the Japan Society of Powder and Powder Metallurgy ◽

10.2497/jjspm.48.779 ◽

2001 ◽

Vol 48 (9) ◽

pp. 779-783

Author(s):

Mamoru Mabuchi

Keyword(s):

High Strain Rate ◽

Strain Rate ◽

Magnesium Alloys ◽

High Strain ◽

High Strength

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Analysis of Plastic Deformation in a Steel Cylinder Striking a Rigid Target

Journal of Applied Mechanics ◽

10.1115/1.4010820 ◽

1954 ◽

Vol 21 (1) ◽

pp. 63-70

Author(s):

E. H. Lee ◽

S. J. Tupper

Keyword(s):

Compression Test ◽

Dynamic Compression ◽

Strain Curve ◽

High Strength ◽

Stress Strain ◽

Steel Cylinder ◽

Theoretical Approaches ◽

Stress Strain Relation ◽

Strength Alloy ◽

Dynamic Yield

Abstract The G. I. Taylor dynamic compression test consists of firing a cylinder of the material to be tested at a target of hardened armor plate, and deducing the dynamic yield stress from the resulting deformation. In the interpretation of the results, interest is concentrated on the wave front of initial plastic straining. The present paper attempts the theoretical determination of the entire strain distribution in such a test cylinder of nickel-chrome steel, this material being chosen since the dynamic influence on the stress-strain relation is likely to be small, thus permitting the static relation to be used in the theory. Strain distributions deduced by two theoretical approaches compare satisfactorily with the distribution of strain obtained in such a dynamic compression test, thus justifying the assumption for this material at the speed considered. The treatment of this problem requires a theory of the propagation of plastic waves, which is developed in this paper, for the particular type of stress-strain curve pertaining to the high-strength alloy steel tested.

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New high-strength magnesium alloys

Metal Powder Report ◽

10.1016/s0026-0657(03)80810-x ◽

2003 ◽

Vol 58 (6) ◽

pp. 50

Keyword(s):

Magnesium Alloys ◽

High Strength

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Comparison of High-Temperature Compression and Compression-Compression Fatigue Behavior of Magnesium Alloys DieMag422 and AE42

Materials ◽

10.3390/ma13030497 ◽

2020 ◽

Vol 13 (3) ◽

pp. 497 ◽

Cited By ~ 2

Author(s):

Mirko Teschke ◽

Alexander Koch ◽

Frank Walther

Keyword(s):

Magnesium Alloys ◽

Elevated Temperatures ◽

Fatigue Behavior ◽

Weight Ratio ◽

High Strength ◽

Fatigue Tests ◽

Fracture Mechanisms ◽

Compression Tests ◽

Computed Tomographic ◽

Tensile Fatigue

Due to their high strength-to-weight-ratio, magnesium alloys are very attractive for use in automotive engineering. For application at elevated temperatures, the alloys must be creep-resistant. Therefore, the influence of the operating temperature on the material properties under quasistatic and cyclic load has to be understood. A previous study investigated tensile-tensile fatigue behavior of the magnesium alloys DieMag422 and AE42 at room temperature (RT). The aim of this study was the comparison of both alloys regarding compression, tensile, and compression-compression fatigue behavior. The quasistatic behavior was determined by means of tensile and compression tests, and the tensile-compression asymmetry was analyzed. In temperature increase fatigue tests (TIFT) and constant amplitude tests (CAT), the temperature influence on the cyclic creeping (ratcheting) behavior was investigated, and mechanisms-relevant test temperatures were determined. Furthermore, characteristic fracture mechanisms were evaluated with investigations of the microstructure and the fracture surfaces. The initial material was analyzed in computed tomographic scans and energy dispersive X-ray (EDX) analyses.

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Effect of Multiwalled Carbon Nanotubes (MWCNTs) on the Micro-Hardness and Corrosion Behaviour Mg-Zn Alloy Prepared by Powder Metallurgy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1000.115 ◽

2020 ◽

Vol 1000 ◽

pp. 115-122

Author(s):

Nono Darsono ◽

Murni Handayani ◽

Franciska Pramuji Lestari ◽

Aprilia Erryani ◽

I Nyoman Gede Putrayasa ◽

...

Keyword(s):

Carbon Nanotubes ◽

Powder Metallurgy ◽

Magnesium Alloys ◽

Corrosion Behaviour ◽

Density Ratio ◽

High Strength ◽

Multiwalled Carbon ◽

Corrosion Properties ◽

Biodegradable Implant ◽

Zn Alloy

Magnesium Alloys have the potential to be applied in the various fields of applications including biomaterials. Magnesium Alloys are an interesting alloy due to its high strength to density ratio. They have been proposed as a biodegradable implant material due to its friendly effect to human body compared to another alloy. Besides its good biodegradable properties, it has a disadvantage of low hardness and corrosion properties. In order to overcome this, it has been combined with other metals such as Zinc (Zn) or Copper (Cu). To increase mechanical properties, we used Carbon Nanotubes (CNT) as reinforcement. Magnesium-Zinc (Mg-xZn) CNTs composites with several compositions was prepared by using powder metallurgy and sintered in the presence of flowing Argon (Ar) gas in tube furnace. Mg-Zn Alloy with the composition of 4% and 6% of Zn and the variation of CNTs at 0.1%, 0.3 %, and 0.5% was also prepared. Hardness testing by using microvickers showed that CNTs can increase the alloy hardness which the maximum hardness is 53.6 HV. The corrosion rates as low as 175.5 mpy exhibited for the Mg-Alloy with the composition of Mg-4-Zn with 0.1 wt.% of CNTs

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