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一、前言近代航空燃气涡轮发动机的特点是不断提高其推力。为此,发动的增压比及涡轮进口温度不断提高。目前有的发动机涡轮进口温度巳达1300℃。但由于现有高温材料工作温度的限制,涡轮进口温度的提高使其冷却技术日益变得非常复杂及不经济。因此对难熔金属作为工程材料日益得到重视。在一九五七年美国召开第一次高温材料会议时,
I. INTRODUCTION The modern aviation gas turbine engine is characterized by continuous improvement of its thrust. To this end, the launch turbocharger ratio and the turbine inlet temperature continues to increase. At present, the engine turbine inlet temperature has reached 1300 ℃. However, due to the existing operating temperature limits of high-temperature materials, the increase of turbine inlet temperature has made its cooling technology increasingly complicated and uneconomical. Therefore, the refractory metal as an engineering material has received increasing attention. When the United States convened the first high temperature materials conference in 1957,