There are two definitions of tungsten alloy: wide tungsten alloy and narrow tungsten alloy: Metal materials containing tungsten are collectively called tungsten alloys, such as tungsten-iron alloy, tungsten-copper alloy, tungsten-nickel alloy, etc.; tungsten narrow alloy: an alloy material composed of tungsten as the base material (including 85% ~ 99% tungsten) and a small amount of nickel (Ni), copper (Cu), iron (Fe), cobalt (Co), molybdenum (Mo), chromium (Cr) and other metal binders, also known as high-density tungsten alloy or high-density tungsten alloy or heavy alloy [1]. The density of tungsten alloy can reach 16.5 ~ 19.0 g/cm^3. The most used are: W-Ni-Cu and W-Ni-Fe two series. This material has notable characteristics in physical properties such as density, strength, hardness, ductility, electrical conductivity/thermal properties and is therefore widely used in defense. Industry, aerospace industry, medical industry, electrical industry and other industries can be divided into two main series, W-Ni-Cu and W-Ni-Fe, as well as W-Ni-Cr, W-Ni-Mo . , W-Ni-Co and other alloys according to their composition. Performance of tungsten alloys.
The physical and mechanical properties of tungsten alloys are mainly the following nine aspects.
High density: The density of high-density tungsten alloys is generally 16.5 ~ 19.0 g/cm^3, which is more than twice the density of steel.
High tensile strength: The tensile strength of high-density sintered W-Ni-Fe alloy is 800~1000MPa, and its strength can be increased to 1300~1500MPa after heat treatment and deformation processing.
Good ductility: W-Ni-Fe high-density alloy has good ductility and its elongation in sintered state can reach 10%~15%. After vacuum or atmosphere dehydrogenation treatment, the elongation can be increased to 20%~30%.
Good ability to absorb radiation: The ability of high-density alloy to absorb radiation is 30% to 40% higher than that of lead, and its stability is also better than that of lead.
Good electrical properties: High-density W-Ni-Cu and W-Ni-Fe alloys have good electrical properties, such as good electrical conductivity, corrosion resistance and high voltage resistance.
Good thermal conductivity and low linear expansion coefficient: Its thermal conductivity is 5 times that of stamped steel and its linear expansion coefficient is only 1/2 ~ 1/3 that of iron or steel.
Good corrosion resistance and oxidation resistance.
Good weldability: High-density alloys can be welded with copper and silver solders and can be electroplated.
Good machining properties: Since the high-density W-Ni-Fe alloy has good ductility, it can be machined by turning, milling, planing, threading and threading, and can also be subjected to large deformation strengthening treatments such as rolling , rotary forging and Forging. Uses of tungsten alloys.
It is mainly used in the following aspects of cutting-edge science and technology, such as the aerospace industry.
1. Gyroscope rotor material. Gyroscopes are the brains of the navigation and control systems of aircraft, satellites, various missiles, spacecraft and nuclear submarines: the stability of gyroscopes increases with increasing weight of the rotating body. Since gyroscope rotors can greatly improve your stability and control accuracy.
2. Inertial rotating elements of aircraft.
3. Balance the weight elements in various instruments and engines, such as the weight elements used in the "Spey" engine and the weight elements that control the throttle and adjust the oil volume at high speed.
In addition, it is also widely used for static and dynamic counterweights on both sides of ailerons and rudders and counterweights for rotating helicopter blades.
In the military field, it is mainly used in the following aspects
1. High-density W-Ni-Fe alloy with very high density, strength, plasticity and hardness is a very critical material in the military industry. It is used as small cluster arrows in gun bullets, in a "powder jacket" form. energy bombs, shotgun shells, submunitions, screen bombs, armor-piercing bombs and has high lethality.
2. In missiles, it is used as gyroscopic rotor of missile instruments, counterweight screws, adjustment plates and high-density alloy missile bodies weighing tens of kilograms.
3. In tank engines, it is used as a counterweight block in
