High temperature alloys in liquid rocket engines are used as fuel injectors for the combustion chamber in the thrust chamber; Turbopump elbow, flange, graphite rudder fasteners, etc. High temperature alloys in liquid rocket engines are used as fuel injector panels in the thrust chamber; Turbopump bend, disc, graphite rudder fasteners, etc. YF73 and YF75 in China use GH3030 alloy wire woven mesh, which is overlapped by 18 layers and then rolled and sintered into porous divergent cooling panels to make combustion chamber injection panels. The turbine rotor began to use GH1040 and GH2038A, and later was forged as a whole with GH4169, machined from the wheel disc, and electrolytic machined from the blades, overcoming the problem of excessive deformation during the GH1040 long test. Comparing the performance of GH1040 and GH4169 alloys, it can be seen that the material requirements for the turbine rotor of a long-range missile engine are met at 800 ℃ 398 MPa for 20 minutes, GH4169 can achieve 30 minutes of stable tissue performance; GH1040 can only maintain for 6 minutes at 800 ℃ and 294MPa, which is not suitable for use requirements. More favorable: from -253 ℃ to room temperature, its strength increases by 392MPa-400MPa, and its plasticity remains basically unchanged, with better low-temperature impact toughness. Therefore, GH4169 is used as a material for important load-bearing components such as turbine rotors, shafts, bushings, and fasteners.

The main materials for the turbine rotor of liquid rocket engines in the United States include intake pipes, turbine blades, and discs. GH1131 alloy is commonly used in China, and the turbine blades depend on the operating temperature. Inconelx should be used in sequence Alloy713c, Astroloy, and Mar-M246; The wheel material includes Inconel718 Waspaloy et al., China mostly adopts GH4169 GH4141 integral turbine, with GH2038A engine shaft.

Small liquid rockets for attitude control of missiles and launch vehicles generally have a small thrust (0.02N-2000N), 100000 pulse starts, a minimum pulse width of a few millimeters per second, a total working time of 5-10 years, and high reliability requirements. The nozzle extension section adopts a radiation cooled single-layer structure, with a simple structure, light weight, and high combustion temperature. The thrust chamber is generally made of niobium based alloy NbHf10-1, and a surface spray antioxidant coating is used to improve performance. The operating temperature is between 1100 ℃ and 1600 ℃, and liquid film cooling is usually used to protect the walls of the combustion chamber. The United States adopts a rhenium iridium alloy combustion chamber with an antioxidant coating, which can eliminate liquid film cooling and significantly improve performance. The combustion chambers of 22N 66N and 445N attitude engines have been successfully developed, and after being put into use, the effective load of satellites and spacecraft has increased by 20 kg-100 kg.

The new generation of launch vehicle engines requires the development and application of new high-temperature alloys that significantly reduce structural weight, replacing some nickel based alloys with Ti Al based alloys. Manufacturing pump housing and low expansion alloy using GH4169.

With the continuous development of the aerospace industry, higher requirements have been put forward for materials in the high-temperature alloy field to meet the needs of various flight missions. This requires us to continuously learn from advanced countries and contribute to the development of national defense technology through our own continuous practice and innovation.

High temperature alloys, also known as thermal strength alloys. According to the matrix organization material, it can be divided into three categories: iron-based nickel based and chromium based. According to production methods, it can be divided into deformed high-temperature alloys and cast high-temperature alloys.

It is an indispensable raw material in the aerospace field. It is a key material for high-temperature parts of aerospace and aviation manufacturing engines. Mainly used for manufacturing combustion chambers, turbine blades, guide vanes, compressors and turbine discs, turbine casings, and other parts. The operating temperature range is between 600 ℃ and 1200 ℃, and the stress and environmental conditions vary depending on the part where the parts are used. There are strict requirements for the mechanical, physical, and chemical properties of the alloy, which are the decisive factors for the performance, reliability, and lifespan of the engine. Therefore, high-temperature alloys are one of the key research projects in the aerospace and national defense fields of developed countries.