The interfacial microstructure and tensile properties of the squeeze cast SiCw/AZ91 Mg composites were characterized. There exist uniform, line and discrete MgO particles at the interface between SiC whisker and magn...The interfacial microstructure and tensile properties of the squeeze cast SiCw/AZ91 Mg composites were characterized. There exist uniform, line and discrete MgO particles at the interface between SiC whisker and magnesium in the composites using acid aluminum phosphate binder. The interfacial reaction products MgO are beneficial to interfacial bonding between SiCw and the Mg matrix. resulting in an improvement of the mechanical properties of the composite.展开更多
There are many Zr particles in as-cast NiAl-33.5Cr-0.5Zr (at. pct) alloy, which usually exist at the edge of eutectic of beta -NiAl and cx-Cr. After air and furnace cooling solution treatments, far 1400 degreesC, 2 h ...There are many Zr particles in as-cast NiAl-33.5Cr-0.5Zr (at. pct) alloy, which usually exist at the edge of eutectic of beta -NiAl and cx-Cr. After air and furnace cooling solution treatments, far 1400 degreesC, 2 h and 1450 degreesC, 1 h, pure Zr phase remains in the furnace cooling (F.C.) state alloys and Ni2AlZr phase forms in the air cooling (A.C.) state alloys. During solution treatment at 1450 degreesC, bulk and 'fish bone' shape Zr-rich phases form respectively in F.C. and A.C. state alloys. A 'river' shape Ni2AlZr phase forms after 1450 C for 1h F.C. and 850 degreesC for 12 h, F.C.. The alloy has less pure Zr and Ni2AlZr phase after 1400 degreesC with both air and furnace cooling followed by 850 C and 950 C for 12 h, F.C. aging treatments, respectively. Additionally, there is a ternary eutectic of NiAlZr and a phase enriched Zr and Cr forms at the edge of the eutectic of beta -NiAl and alpha -Cr in the alloy treated at 1400 degreesC, 2 h, F.C. and 950 degreesC, 12 h, F.C.展开更多
基金National Natllral S(tience l.'oundation of China (No. 59631080).
文摘The interfacial microstructure and tensile properties of the squeeze cast SiCw/AZ91 Mg composites were characterized. There exist uniform, line and discrete MgO particles at the interface between SiC whisker and magnesium in the composites using acid aluminum phosphate binder. The interfacial reaction products MgO are beneficial to interfacial bonding between SiCw and the Mg matrix. resulting in an improvement of the mechanical properties of the composite.
基金The work was supported by the National Advanced Materials Connittee of China(Grant No.970321016)the National Natural Science Foundation of Chind(No.59895152).
文摘There are many Zr particles in as-cast NiAl-33.5Cr-0.5Zr (at. pct) alloy, which usually exist at the edge of eutectic of beta -NiAl and cx-Cr. After air and furnace cooling solution treatments, far 1400 degreesC, 2 h and 1450 degreesC, 1 h, pure Zr phase remains in the furnace cooling (F.C.) state alloys and Ni2AlZr phase forms in the air cooling (A.C.) state alloys. During solution treatment at 1450 degreesC, bulk and 'fish bone' shape Zr-rich phases form respectively in F.C. and A.C. state alloys. A 'river' shape Ni2AlZr phase forms after 1450 C for 1h F.C. and 850 degreesC for 12 h, F.C.. The alloy has less pure Zr and Ni2AlZr phase after 1400 degreesC with both air and furnace cooling followed by 850 C and 950 C for 12 h, F.C. aging treatments, respectively. Additionally, there is a ternary eutectic of NiAlZr and a phase enriched Zr and Cr forms at the edge of the eutectic of beta -NiAl and alpha -Cr in the alloy treated at 1400 degreesC, 2 h, F.C. and 950 degreesC, 12 h, F.C.
