Effect of Al contents on microstructures, tensile and creep properties of Mg–Al–Sr–Ca alloy

Bai, Jing; Yangshan, Sun; Xue, Feng; Xue, Songbai; Qiang, Jing; Zhu, Tao

doi:10.1016/j.jallcom.2006.07.096

Cited by 58 publications

(26 citation statements)

References 11 publications

(16 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The creep properties of heat resistant magnesium alloy are usually described by the secondary creep rate and creep strain of 100 hours [1,5,[17][18][19] , therefore, the comparison between different heat resistant magnesium alloys is necessary. Table 2 summarizes the most important RE-free magnesium alloys, including the famous MRI230D [5] , AJX series [17,18] alloys.…”

Section: Creep Properties Of As-cast Axt552 Alloymentioning

confidence: 99%

“…Table 2 summarizes the most important RE-free magnesium alloys, including the famous MRI230D [5] , AJX series [17,18] alloys. In order to narrow the difference in experimental conditions, only those with similar creep experimental conditions are given in Table 2, including the present study on AXT552 alloys crept at conditions of 175°C/75MPa and 200°C/60MPa for comparison.…”

Section: Creep Properties Of As-cast Axt552 Alloymentioning

confidence: 99%

See 1 more Smart Citation

Creep resistance of as-cast Mg-5Al-5Ca-2Sn alloy

et al. 2017

View full text Add to dashboard Cite

I ncreasing attention has been paid due to increased demand of heat resistant magnesium alloys by heatresistant parts, such as powertrain and transmission components [1] for lightweight vehicles. Mg-Al system is one focus for development of this kind of materials. In alloying elements, calcium makes a most attractive option since it provides acceptable levels of castability and increased corrosion and creep resistance at low cost in comparison with RE [2][3][4] . The addition of Ca to the MgAl system resulted in high pressure die casting MRI230D and MRI153 alloys, both of which present significantly better creep resistance than AE42 alloy [5,6] . Mg-Sn-based alloys have great potential for creep resistance because of the formation of thermally stable Mg 2 Sn phase in the as-cast condition, and many Ca-containing Mg-Sn alloys exhibit good creep resistance [4,[7][8][9][10][11] . Therefore, the consideration for the development of Mg-Al-Sn-Ca alloy becomes necessary. In our previous studies, Mg-5Al-5Ca-2Sn (AXT552) presents good thermal stability [12] due to the formation of connected hard skeleton [13] composed of Abstract: In the present study, creep properties of as-cast Mg-5Al-5Ca-2Sn (AXT552) alloy were investigated by means of a GWT304 creep testing machine at temperatures of 175 °C and 200 °C in the stress range of 35-90 MPa. Results show that creep rates increase with applied stress at an identical temperature. Creep strain at 100 hours is 0.0518% and 0.083% at creep conditions of 175°C/75MPa and 200°C/60MPa, respectively, which is comparable to MRI230D and much lower than most of AX series alloys. By the observation and analysis for samples before and after creep tests using a Shimadzu XRD-7000 type X-ray diffractometer (XRD) and a Hitachi S-3400N type scanning electron microscope (SEM), it was found that Al 2 Ca (C15) phase precipitated out of C36 phase or matrix. The cavity formation and connection at the interface of soft matrix and hard intermetallics caused the propagation of cracking along the eutectic phase during creep process and dislocation accommodated grain/ phase boundary sliding is expected to be the dominant creep mechanism.Key words: as-cast AXT552 alloy; creep properties; creep rate; creep strain; microstructure Al 2 Ca and (Mg,Al) 2 Ca compounds. It was found that the skeleton is able to effectively shield load from the softer α-Mg matrix [14] and increase the creep resistance of the alloys [15,16] . Therefore, the tensile creep property of ascast AXT552 alloy at temperatures of 175 °C and 200 °C was checked and compared with other heat-resistant Mg alloys in this study. Experimental procedureMg-5Al-5Ca-2Sn (wt.%), or AXT552, alloy was prepared using commercial Mg, Al, Sn (with purity of 99.9%) metals and Mg-20Ca master alloy. The alloy was melted in a mild steel crucible under the protection of a mixed gas atmosphere of 1% SF 6 and 99% Ar. After the master alloy added was melted, the melt was held at 750 °C for 10 min, and then poured into a cylindrical mold made of cast iron with a diam...

show abstract

Section: Creep Properties Of As-cast Axt552 Alloymentioning

confidence: 99%

Section: Creep Properties Of As-cast Axt552 Alloymentioning

confidence: 99%

Creep resistance of as-cast Mg-5Al-5Ca-2Sn alloy

et al. 2017

View full text Add to dashboard Cite

show abstract

“…1). In addition, Bai et al 12) investigated the effect of extrusion process on microstructures and mechanical properties of Mg-4Al-2Sr (AJ42) and Mg-4Al-2Sr-1Ca (AJC421) alloys, and found that the creep resistances of both alloys were obviously reduced after extrusion deformation. Zuzanka et al 13) investigated the deformation behavior of the ternary magnesium alloy, Mg5Al-0.6Sr (AJ50), in uniaxial tension tests at temperatures between 20 C and 300 C and at an initial strain rate ranging in the order of 10 À5 s À1 , and found that the yield stress as well as the maximum stress of the alloy were very sensitive to the testing temperature (Fig.…”

Section: Mechanical Properties Of New Type Magnesium Alloys Containinmentioning

confidence: 99%

“…[1][2][3][4] Therefore, a lot of ways are being investigated in the world in order to further improve the mechanical properties and processing performances of the magnesium alloys. [5][6][7][8][9][10][11][12][13][14][15][16] Alloying is an important method used by many researchers. In recent years, Mg-Al-Sr alloy system has emerged as potential heat-resistant Mg-alloys.…”

Section: Introductionmentioning

confidence: 99%

Mechanical Properties and Microstructure of Magnesium-Aluminum Based Alloys Containing Strontium

et al. 2008

View full text Add to dashboard Cite

The mechanical properties and processing performances of conventional magnesium alloys still could not meet the need of important application fields due to some demerits, such as poor formability, low creep resistance and unsatisfactory strength at elevated temperature. Recent investigations have shown that additions of strontium to magnesium alloys are effective in improving creep resistance of the alloys at temperatures above 150 C, and some new types of magnesium alloys containing strontium have been developed. The mechanical properties and microstructure of magnesium-aluminum based alloys containing strontium are reviewed, and the considerable discrepancy among the research results is discussed. Special attentions are paid to the mechanical properties, compounds and grain refinement of Mg-Al-Sr based alloys. The Sr/Al ratio is thought to be important to control the microstructure of Mg-Al-Sr alloys. The mechanism of grain refinement caused by strontium addition in magnesium alloys remains unclear.

show abstract

“…In particular, Mg-Al-Ca alloys have high heat resistance [7][8][9][10] and resist combustion upon the addition of calcium 11,12) . However, there is concern that cast cracking can easily occur as a result of calcium addition 13) .…”

Section: Introductionmentioning

confidence: 99%

Effect of Tin Addition on Inhibition of Cast Cracking in Mg-Al-Ca Alloys

et al. 2016

View full text Add to dashboard Cite

In a previous study, we reported that adding tin to Mg-Al-Ca alloys inhibits cast cracking while maintaining excellent heat resistance. In this study, to clarify the mechanism resulting in the improved castability, Mg-Al-Ca alloys with different compositions were cast by high-pressure die casting into an I-shaped die with strain gauge instrumentation. The solidi cation shrinkage and thermal contraction of the alloys during the solidi cation and cooling process were investigated. The addition of tin decreased the solidi cation shrinkage of the alloys, and the tensile stress in the alloys was relaxed. On the basis of these results, the addition of tin is considered to improve the castability.

show abstract

Effect of Al contents on microstructures, tensile and creep properties of Mg–Al–Sr–Ca alloy

Cited by 58 publications

References 11 publications

Creep resistance of as-cast Mg-5Al-5Ca-2Sn alloy

Creep resistance of as-cast Mg-5Al-5Ca-2Sn alloy

Mechanical Properties and Microstructure of Magnesium-Aluminum Based Alloys Containing Strontium

Effect of Tin Addition on Inhibition of Cast Cracking in Mg-Al-Ca Alloys

Contact Info

Product

Resources

About