The Experts below are selected from a list of 96 Experts worldwide ranked by ideXlab platform
K Hono - One of the best experts on this subject based on the ideXlab platform.
-
strong and ductile heat treatable mg sn zn al wrought Alloys
Acta Materialia, 2015Co-Authors: Takayoshi Sasaki, Shigeharu Kamado, K Hono, F R Elsayed, T Nakata, T OhkuboAbstract:Abstract A newly developed Mg–Sn–Zn–Al based Alloy shows substantial strengthening by artificial aging. A Na-doped Mg–5.4Sn–4.2Zn–2.0Al–0.2Mn–0.1Na (TZAM5420−0.1Na) (wt.%) Alloy exhibited a significant increase in yield strength from 243 to 347 MPa by a T6 treatment due to the uniform dispersion of nanoscale precipitates by aging. The trace addition of Na causes the formation of Sn–Na co-clusters in the early stage of aging, which provides heterogeneous nucleation sites for Mg 2 Sn precipitates. However, Na strongly segregates at grain boundaries and this degrades the ductility significantly. To overcome this problem, we developed a Na-free Mg–6.6Sn–5.9Zn–2.0Al–0.2Mn (TZAM6620) Alloy, in which nano-scale MgZn 2 precipitates are uniformly dispersed by double aging. Pre-aging caused the formation of Zn-rich Guinier Preston zones, which acted as heterogeneous nucleation sites for the MgZn 2 precipitates. The double-aged TZAM6620 Alloy exhibited a very high yield strength of 370 MPa with large elongation of 14%.
-
a high strength mg sn zn al Alloy extruded at low temperature
Scripta Materialia, 2008Co-Authors: Tomoyuki Sasaki, Shigeharu Kamado, K Yamamoto, T Honma, K HonoAbstract:We report a new Mg–Sn–Zn–Al-Based Alloy that is suitable for extrusion to give a high-strength. The extruded Alloy exhibited high yield strengths of 308 MPa in tension and 280 MPa in compression, to give a tension to compression ratio of 0.9. The extruded Alloy consists of coarse and fine-grains with a basal texture, which gives rise to the high tension to compression ratio. The fine microstructure is attributed to the dynamic recrystallization and precipitation that occur during the extrusion.
Shigeharu Kamado - One of the best experts on this subject based on the ideXlab platform.
-
strong and ductile heat treatable mg sn zn al wrought Alloys
Acta Materialia, 2015Co-Authors: Takayoshi Sasaki, Shigeharu Kamado, K Hono, F R Elsayed, T Nakata, T OhkuboAbstract:Abstract A newly developed Mg–Sn–Zn–Al based Alloy shows substantial strengthening by artificial aging. A Na-doped Mg–5.4Sn–4.2Zn–2.0Al–0.2Mn–0.1Na (TZAM5420−0.1Na) (wt.%) Alloy exhibited a significant increase in yield strength from 243 to 347 MPa by a T6 treatment due to the uniform dispersion of nanoscale precipitates by aging. The trace addition of Na causes the formation of Sn–Na co-clusters in the early stage of aging, which provides heterogeneous nucleation sites for Mg 2 Sn precipitates. However, Na strongly segregates at grain boundaries and this degrades the ductility significantly. To overcome this problem, we developed a Na-free Mg–6.6Sn–5.9Zn–2.0Al–0.2Mn (TZAM6620) Alloy, in which nano-scale MgZn 2 precipitates are uniformly dispersed by double aging. Pre-aging caused the formation of Zn-rich Guinier Preston zones, which acted as heterogeneous nucleation sites for the MgZn 2 precipitates. The double-aged TZAM6620 Alloy exhibited a very high yield strength of 370 MPa with large elongation of 14%.
-
a high strength mg sn zn al Alloy extruded at low temperature
Scripta Materialia, 2008Co-Authors: Tomoyuki Sasaki, Shigeharu Kamado, K Yamamoto, T Honma, K HonoAbstract:We report a new Mg–Sn–Zn–Al-Based Alloy that is suitable for extrusion to give a high-strength. The extruded Alloy exhibited high yield strengths of 308 MPa in tension and 280 MPa in compression, to give a tension to compression ratio of 0.9. The extruded Alloy consists of coarse and fine-grains with a basal texture, which gives rise to the high tension to compression ratio. The fine microstructure is attributed to the dynamic recrystallization and precipitation that occur during the extrusion.
W Lee - One of the best experts on this subject based on the ideXlab platform.
-
exothermic reaction in eutectoid zn al based Alloys
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 1999Co-Authors: Yimei Zhu, W LeeAbstract:Abstract Both solution treated and quench-aged eutectoid Zn–Al based Alloys (ZnAl20Cu3Si2 and ZnAl22Cu2 in wt.%) were studied by differential scanning calorimeter (DSC), X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. An exothermic phenomenon was observed at the early stage of ageing. Similar behavior was also found for the cast eutectoid Zn–Al Alloy. The activation energy for the exothermic phenomenon was calculated, which was in a good agreement with that derived from X-ray diffraction examination for the decomposition of the supersaturated β ′ s phase in the eutectoid Zn–Al based Alloy. It is concluded that the decomposition of the β ′ s phase is an exothermic solid state reaction in the eutectoid Zn–Al based Alloys.
Wu Dengyun - One of the best experts on this subject based on the ideXlab platform.
-
Microstructure and mechanical properties of Mg–Al based Alloy with calcium and rare earth additions
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2003Co-Authors: Du Wenwen, Sun Yangshan, Min Xuegang, Xue Feng, Wu DengyunAbstract:Abstract Effects of calcium and rare earth additions to Alloy AZ91 on the microstructure and mechanical properties were investigated. The results indicated that small amounts of calcium addition to AZ91 did not cause the formation of any new phases in the microstructure, but refined the as-cast microstructure and increased the thermal stability of the β phase so that the yield strength and creep resistance of the Alloy were significantly improved. Additions of lanthanum-rich misch metal (MM) resulted in the formation of needle-shaped particles, which showed very high thermal stability and did not dissolve into the matrix after the solution treatment at 420 °C for 20 h. The strength as well as creep resistance of the Alloy at elevated temperatures was remarkably increased when MM was added combined with calcium. The highest creep resistance was obtained from the Alloy with 3% of MM and 0.3% of calcium addition and its steady state creep rate reached as low as 2.69×10 −8 s −1 , one order of magnitude lower than that of Alloy AZ91 without MM and calcium additions.
F R Elsayed - One of the best experts on this subject based on the ideXlab platform.
-
strong and ductile heat treatable mg sn zn al wrought Alloys
Acta Materialia, 2015Co-Authors: Takayoshi Sasaki, Shigeharu Kamado, K Hono, F R Elsayed, T Nakata, T OhkuboAbstract:Abstract A newly developed Mg–Sn–Zn–Al based Alloy shows substantial strengthening by artificial aging. A Na-doped Mg–5.4Sn–4.2Zn–2.0Al–0.2Mn–0.1Na (TZAM5420−0.1Na) (wt.%) Alloy exhibited a significant increase in yield strength from 243 to 347 MPa by a T6 treatment due to the uniform dispersion of nanoscale precipitates by aging. The trace addition of Na causes the formation of Sn–Na co-clusters in the early stage of aging, which provides heterogeneous nucleation sites for Mg 2 Sn precipitates. However, Na strongly segregates at grain boundaries and this degrades the ductility significantly. To overcome this problem, we developed a Na-free Mg–6.6Sn–5.9Zn–2.0Al–0.2Mn (TZAM6620) Alloy, in which nano-scale MgZn 2 precipitates are uniformly dispersed by double aging. Pre-aging caused the formation of Zn-rich Guinier Preston zones, which acted as heterogeneous nucleation sites for the MgZn 2 precipitates. The double-aged TZAM6620 Alloy exhibited a very high yield strength of 370 MPa with large elongation of 14%.