Effects of Isothermal Heating Process and Rare Earth Elements Addition on the Mechanical Properties of Semi-Solid Formed Mg-5%Zn Alloys

2007 ◽  
Vol 544-545 ◽  
pp. 279-282
Author(s):  
Jeong Min Kim ◽  
Joong Hwan Jun ◽  
Ki Tae Kim ◽  
Woon Jae Jung
Keyword(s):  
Mechanical Properties ◽  
High Thermal Stability ◽  
Heating Process ◽  
Isothermal Heating ◽  
Step Heating ◽  
One Step ◽  
Semi Solid ◽  
Zn Alloys ◽  
Zr Alloy ◽  
Zr Alloys

Two-step isothermal heating and conventional one-step heating processes were used to produce the semi-solid slurry of Mg-5%Zn-0.5%Zr alloys with and without 1%RE. It was found that the slurry with better semi-solid characteristics could be fabricated by the two-step heating compared to the conventional process. Only the small amount of RE addition to the Mg-5%Zn- 0.5%Zr alloy was observed to reduce the solid particle size of slurry significantly and to improve the tensile strength at 150oC, probably owing to Mg-Zn-RE phase with a high thermal stability.

Steel Grades Adapted to the Thixoforging Process: Metallurgical Structures and Mechanical Properties

2006 ◽  
Vol 116-117 ◽  
pp. 712-716 ◽  
Author(s):  
Marc Robelet ◽  
Ahmed Rassili ◽  
Dirk Fischer
Keyword(s):  
Mechanical Properties ◽  
Liquid Fraction ◽  
Solidus Temperature ◽  
Process Temperature ◽  
Heating Process ◽  
Work Piece ◽  
Inductive Heating ◽  
Steel Grades ◽  
Automotive Part ◽  
Semi Solid

Thixoforming of steel offers the advantages of casting technology in combination with high mechanical strength that can only be achieved by forging. The progress in establishing this technology in industry depends on the success in the development of suitable steel grades. Recent investigations dealt with the development of steel grades that are especially adapted to the thixoforming process. For this, alloys were developed with a lower solidus temperature and a wider process temperature range compared to classic forging steels. In consequence, the inductive heating process is more tolerant to inaccuracies and for a given liquid fraction the process temperature window is easier to handle. It is desired to obtain great degrees of deformation at rather low forming forces as these parameters determine the size of the needed presses. This behaviour is affected by the present liquid fraction in the slug and the heat transfer between work piece and die. It was detected that variations of the forming force have a direct influence on the quality of the thixoformed parts. In order to make the thixoforming technology of steels competitive versus other forming technologies, the parts must show a favourable microstructure and thus, good in-use properties. In this paper various solutions are compared. The main results obtained in the optimization research, namely, the steel grades adapted to semi-solid forming, the resulting process parameters and the mechanical properties of thixoforming parts will be presented for two exemplary steel grades. By producing a real automotive part, thixoforging of steels with regard to the adapted materials and to the ongoing industrial implementation of this process is proved.

scholarly journals Mechanical and Thermal Conductivity Properties of Enhanced Phases in Mg-Zn-Zr System from First Principles

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2010
Author(s):  
Shuo Wang ◽  
Yuhong Zhao ◽  
Huijun Guo ◽  
Feifei Lan ◽  
Hua Hou
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Shear Modulus ◽  
Bulk Modulus ◽  
Intermetallic Compounds ◽  
Elastic Constants ◽  
First Principles ◽  
Strengthening Phases ◽  
Zr Alloy ◽  
Zr Alloys

In this paper, the mechanical properties and minimum thermal conductivity of ZnZr, Zn2Zr, Zn2Zr3, and MgZn2 are calculated from first principles. The results show that the considered Zn-Zr intermetallic compounds are effective strengthening phases compared to MgZn2 based on the calculated elastic constants and polycrystalline bulk modulus B, shear modulus G, and Young’s modulus E. Meanwhile, the strong Zn-Zr ionic bondings in ZnZr, Zn2Zr, and Zn2Zr3 alloys lead to the characteristics of a higher modulus but lower ductility than the MgZn2 alloy. The minimum thermal conductivity of ZnZr, Zn2Zr, Zn2Zr3, and MgZn2 is 0.48, 0.67, 0.68, and 0.49 W m−1 K−1, respectively, indicating that the thermal conductivity of the Mg-Zn-Zr alloy could be improved as the precipitation of Zn atoms from the α-Mg matrix to form the considered Zn-Zr binary alloys. Based on the analysis of the directional dependence of the minimum thermal conductivity, the minimum thermal conductivity in the direction of [110] can be identified as a crucial short limit for the considered Zn-Zr intermetallic compounds in Mg-Zn-Zr alloys.

Phase Stability and Mechanical Properties of Ti-Cr-Sn-Zr Alloys Containing a Large Amount of Zr

2016 ◽  
Vol 879 ◽  
pp. 1344-1349 ◽  
Author(s):  
Yonosuke Murayama ◽  
Erdnechuluun Enkhjavkhlan ◽  
Akihiko Chiba
Keyword(s):  
Mechanical Properties ◽  
Young’S Modulus ◽  
Deformation Behavior ◽  
Single Phase ◽  
Young's Modulus ◽  
Martensitic Structure ◽  
Β Phase ◽  
Microstructural Transition ◽  
Zr Alloy ◽  
Zr Alloys

The Young’s modulus of Ti-Cr-Sn-Zr alloy varies with the composition of Cr, Sn and Zr, in which the elements act as β stabilizers. Some Ti-Cr-Sn-Zr alloys show very low Young’s modulus under 50GPa. The amount of Zr in alloys with very low Young's modulus increases with the decrease of Cr. We investigated the Young’s modulus and deformation behavior of Ti-xCr-Sn-Zr (x=0~1mass%) alloys containing a large amount of Zr. The quenched microstructure of Ti-Cr-Sn-Zr alloys changes from martensitic structure to β single-phase structure if the amounts of β stabilized elements are increased. The Ti-Cr-Sn-Zr alloys with compositions close to the transitional composition of microstructure from martensite to β phase show minimum Young’s modulus. The clear microstructural transition disappears and the minimum Young’s modulus increases if the amount of Cr becomes too small. In Ti-Cr-Sn-Zr alloys containing a large amount of Zr, Young’s modulus depends on β phase that is intermingled with martensite.

Mechanical Properties of Ti-Cr-Sn-Zr Alloys

2010 ◽  
Vol 638-642 ◽  
pp. 635-640 ◽  
Author(s):  
Yonosuke Murayama ◽  
Shuichi Sasaki ◽  
Hisamichi Kimura ◽  
Akihiko Chiba
Keyword(s):  
Mechanical Properties ◽  
Young’S Modulus ◽  
Biomedical Application ◽  
Young's Modulus ◽  
Mechanical Twinning ◽  
Β Phase ◽  
Low Modulus ◽  
Deformation Modes ◽  
Zr Alloy ◽  
Zr Alloys

Low modulus β Ti alloys are attractive for biomedical application. This work examines the mechanical properties of Ti-Cr-Sn-Zr system alloys, especially the effect of the varying alloy composition on the microstructure, the Young’s modulus and the deformation mechanism.The Young’s modulus of the alloy varies with the composition, which variation is caused mainly from the competition between the meta-stable β phase and ω phase.The deformation modes of the Ti-Cr-Sn-Zr alloy, which are the mechanical twinning, the deformation by slip and the deformation-induced transformation, also change depending on the composition of the alloy. The minimum of the Young’s modulusof the Ti-Cr-Sn-Zr alloy in this experiment was shown in the composition where the microstructure of the alloy changes from the martensitic structure to the meta-stable β structure.

Mechanical Properties and Creep Behavior of Mg-Gd-Y-Zr Alloys

2007 ◽  
Vol 546-549 ◽  
pp. 163-166 ◽  
Author(s):  
Yan Gao ◽  
Qu Dong Wang ◽  
Jin Hai Gu ◽  
Yang Zhao ◽  
Yan Tong
Keyword(s):  
Mechanical Properties ◽  
Tensile Properties ◽  
Creep Behavior ◽  
Creep Resistance ◽  
Different Temperatures ◽  
Cast Condition ◽  
Better Than ◽  
Zr Alloy ◽  
Zr Alloys

The microstructure, mechanical properties and creep behavior of Mg-Gd-Y-Zr alloys at different temperatures and stresses have been investigated. Results show that the tensile properties and creep resistance at T6 condition is much higher than that at as-cast condition. The creep resistance of Mg-Gd-Y-Zr alloy at 250°C/80MPa is markedly better than that at 300°C/50MPa, indicating that temperature makes more effects on the creep resistance than the stress.

Influence of Electromagnetic Force on Solidification of Cu-Cr-Zr Alloy

2015 ◽  
Vol 817 ◽  
pp. 545-549 ◽  
Author(s):  
Wen Bin Wang ◽  
Lin Zhang ◽  
Chong Luo ◽  
En Gang Wang
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Electromagnetic Force ◽  
Experimental Results ◽  
Electromagnetic Stirring ◽  
Second Phase ◽  
And Performance ◽  
Zr Alloy ◽  
Zr Alloys

In order to improve the distribution of second phase and performance the Cu-Cr-Zr alloy was processed by solidification under the effect of electromagnetic stirring (EMS) and in situ drawing deformation. Study of Cu-Cr-Zr conductivity and mechanical properties under different deformation strains was also carried out, to analyze the effect of EMS on Cu-Cr-Zr alloys. The experimental results showed that the Cr dendrites tended to be smaller and shorter in Cu-10Cr-0.1Zr alloy solidified with EMS (16Hz, 100A). Since electromagnetic stirring have the role to break dendrite,it’s beneficial to increase the amount of dendrites and decrease the size of dendrites. The tensile strength of Cu-10Cr-0.1Zr wire solidified with EMS was higher than that solidified without EMS.

Microstructure and Mechanical Properties of Mg-Gd-Sm-Zr Alloy

2007 ◽  
Vol 546-549 ◽  
pp. 159-162 ◽  
Author(s):  
Yang Zhao ◽  
Qu Dong Wang ◽  
Jin Hai Gu ◽  
Yan Gao ◽  
Yan Tong
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Ultimate Tensile Strength ◽  
Yield Strength ◽  
Xrd Analysis ◽  
Microstructure And Mechanical Properties ◽  
Better Than ◽  
Zr Alloy ◽  
Zr Alloys

Microstructure and mechanical properties of three kinds of Mg-Gd-Sm-Zr alloys have been analyzed in this paper. Results exhibit that the microstructure of as-cast Mg-Gd-Sm-Zr alloy contains α-Mg and eutectic compounds which are mainly comprised of most Mg5Gd-base phases and a few Mg41Sm5-base phases by EDX and XRD analysis. Ultimate tensile strength and yield strength of the alloys can be significantly improved after T6 treatment. Mechanical properties of studied alloys in T6 condition are better than that of WE54-T6 alloy.

Research into the Aluminum-Zirconium Alloys Dedicated for Electirical Purposes

2015 ◽  
Vol 641 ◽  
pp. 47-55 ◽  
Author(s):  
Marzena Piwowarska-Uliasz ◽  
Tadeusz Knych ◽  
Piotr Uliasz
Keyword(s):  
Mechanical Properties ◽  
Production Technology ◽  
Subject Matter ◽  
Zirconium Alloys ◽  
Microstructure Analysis ◽  
Processing Technology ◽  
Zirconium Content ◽  
Production Technologies ◽  
Zr Alloy ◽  
Zr Alloys

The discussed subject matter concerns the influence of two kinds of Al-Zr alloy production technologies on the properties of the wires dedicated for electrical purposes. The paper presents research and the analysis of the research into the influence of the production technology and the processing technology on the ingot wires made from the heat resistant Al-Zr alloys as well as on the characteristics of the properties of the examined materials with the focus on the electrical and mechanical properties and their microstructure analysis. The materials subject to the mechanical and physicochemical research were materials manufactured in industrial and laboratory conditions in the form of the wire rod and cast bars as well as wires of various diameters drawn from them. The research concerned six Al-Zr alloys with the zirconium content from 0.05 to 0.32% of the mass.

Microstructure and Mechanical Properties of Cast and Semi-Solid Formed Mg-Al-Zn Alloys

2006 ◽  
Vol 116-117 ◽  
pp. 288-291 ◽  
Author(s):  
Jeong Min Kim ◽  
Bong Koo Park ◽  
Joong Hwan Jun ◽  
Ki Tae Kim ◽  
Woon Jae Jung
Keyword(s):  
Mechanical Properties ◽  
Grain Boundary ◽  
Tensile Properties ◽  
Room Temperature ◽  
Forming Process ◽  
Microstructure And Mechanical Properties ◽  
Cast Alloys ◽  
Semi Solid ◽  
Zn Alloys ◽  
Conventionally Cast

Various Mg-Al-Zn alloys with different Al and Zn contents were fabricated by conventional casting and semi-solid forming process. And the microstructure and mechanical properties of the alloys were investigated. In Mg-4%Al-(5~7)%Zn alloys most of the grain boundary phases were found to be Mg-Al-Zn while in Mg-6%Al or Mg-8%Al based alloys the Mg- Al-Zn phase coexisted with Mg17Al12 at grain boundaries. At room temperature the semi-solid formed alloys showed significantly higher tensile properties, especially elongation, than the conventionally cast alloys.

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