Usually include magnetic alloys (see magnetic materials), elastic alloys, expansion alloys, thermal bimetals, electrical alloys, hydrogen storage alloys (see hydrogen storage materials), shape memory alloys, magnetostrictive alloys (see magnetostrictive materials), etc. .
In addition, some new alloys are often included in the category of precision alloys in practical applications, such as damping and vibration reduction alloys, stealth alloys (see stealth materials), magnetic recording alloys, superconducting alloys, microcrystalline amorphous alloys, etc.
Precision alloys are divided into seven categories according to their different physical properties, namely: soft magnetic alloys, deformed permanent magnetic alloys, elastic alloys, expansion alloys, thermal bimetals, resistance alloys, and thermoelectric corner alloys.
The vast majority of precision alloys are based on ferrous metals, only a few are based on non-ferrous metals
Magnetic alloys include soft magnetic alloys and hard magnetic alloys (also known as permanent magnetic alloys). The former has a low coercive force (m), while the latter has a large coercive force (>104A/m). Commonly used are industrial pure iron, electrical steel, iron-nickel alloy, iron-aluminum alloy, alnico alloy, rare earth cobalt alloy, etc.
Thermal bimetal is a composite material composed of two or more layers of metals or alloys with different expansion coefficients that are firmly bonded to each other along the entire contact surface. The high-expansion alloy is used as the active layer, the low-expansion alloy is used as the passive layer, and an interlayer can be added in the middle. As the temperature changes, the thermal bimetal can bend, and is used to manufacture thermal relays, circuit breakers, household appliance starters, and liquid and gas control valves for the chemical industry and power industry.
Electrical alloys include precision resistance alloys, electrothermal alloys, thermocouple materials and electrical contact materials, etc., and are widely used in the fields of electrical devices, instruments and meters.
Magnetostrictive alloys are a class of metal materials with magnetostrictive effects. Commonly used are iron-based alloys and nickel-based alloys, which are used to manufacture ultrasonic and underwater acoustic transducers, oscillators, filters and sensors.
1. When choosing a precision alloy smelting method, it is necessary to comprehensively consider the quality, furnace batch cost, etc., in most cases. Such as requiring ultra-low carbon precise control of ingredients, degassing, improving purity, etc. It is an ideal way to use the electric arc furnace plus refining outside the furnace. Under the premise of high quality requirements, the vacuum induction furnace is still a good method. However, the larger capacity should be used as much as possible.
2. Attention should be paid to pouring technology to prevent contamination of molten steel during pouring, and horizontal continuous pouring has unique significance for precision alloys