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The service performance and operation life of thermal barrier coatings are closely related to the phase composition and structure of the bond coat alloy， which is directly determined by its composition. In this work， the effects of the basic elements Co and Al and the modified element Zr on the precipitation behavior of equilibrium phases are analyzed by Thermo-Calc software. Then， the influence of Zr content on phase composition and Zr-rich phase distribution of NiCoCrAlY bond coat alloy is investigated using an X-ray diffractometer and a field emission scanning electron microscope. Thermodynamic calculation results show that the σ-CoCr phase begins to precipitate in the alloy with 10%（mass fraction， the same below）Co， and the maximum precipitation amount （mole fraction） of σ-CoCr phase increases from 0.055 to 0.229 when the Co content increases from 10% to 16%， and it exists in the high-temperature service range of coatings with Co content exceeding 14%. When the Al content is 8%-10%， the γ-Ni phase precipitates from the liquid before the β-NiAl phase， which is opposite in the alloys containing 12%-16%Al. Moreover， with the increase of Al content from 8% to 16%， the solidification interval significantly enlarges from 75 ℃ to 171 ℃， and the β-NiAl content continuously increases. When the Zr content increases from 0.15% to 1.0%， the liquidus temperature obviously decreases from 1264 ℃ to 1136 ℃， and the solidification temperature range enlarges from 151 ℃ to 275 ℃. In addition， the non-equilibrium phase composition at room temperature of the bond coat alloy designed based on thermodynamic calculation is composed of β-NiAl and γ'-Ni3Al matrix phases， and a small amount of α-Cr precipitate on the matrix. Meanwhile， Ni5Y is distributed surrounding γ'-Ni3Al phase. For the alloy containing 0.5% and 1.0%Zr， the precipitation position of H_L21 phase is different. This Zr-rich phase mainly precipitates at the interface of β-NiAl/γ'-Ni3Al for the former， while it also precipitates on the β-NiAl matrix phase for the latter.
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| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |
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