Shaped Spring Steel Wire Characteristics Of The Use

Shaped Spring Steel Wire characteristics of the use
Shaped Spring Steel Wire used in the elastic range, after unloading should be restored to the original position, the plastic deformation of the smaller the better, so the wire should have a high elastic limit, yield strength and tensile strength. The higher the flexion ratio, the closer the elastic limit is to the tensile strength, and thus the greater the strength utilization, the stronger the elasticity of the spring formed.
Shaped Spring Steel Wire to rely on elastic deformation to absorb the impact energy, so the shape of the spring wire does not have to have a high plasticity, but at least have to bear the shape of spring steel forming plastic, and enough to withstand the impact of energy toughness.
Shaped Spring Steel Wire is usually under the action of alternating stress long-term work, so have a very high fatigue limit, and good anti-creep and anti-relaxation performance.
In the specific environment used in the spring-shaped wire, the wire will have some special requirements, such as: corrosive media used in the spring-shaped wire, must have good corrosion resistance. Precision instruments used in the spring-shaped wire, should have long-term stability and sensitivity, the temperature coefficient is low, the quality factor to be high, the effect is small, the elastic modulus to be constant. In the high temperature conditions of the Shaped Spring Steel Wire, requiring high temperature can still maintain sufficient flexibility and good creep resistance and so on.
In addition, should also be considered Shaped Spring Steel Wire forming process and heat treatment process. Cold drawn spring steel wire and oil quenched and tempered spring steel wire are supplied in the state of steel wire directly around the Shaped Spring Steel Wire, Shaped Spring Steel Wire after forming the stress to deal with the direct use of stress. The tensile strength of the cold drawn spring wire is slightly higher than that of the oil quenched and tempered wire. Large-scale cold-drawn steel wire elasticity is too large, around the wound spring wire is very difficult, so the use of cold drawn spring wire specifications generally less than 8.0mm, oil quenching and tempering steel wire specifications generally less than 13.0mm. In fact the diameter of 13.0mm-shaped spring steel wire and more use of light-pull state-shaped spring steel wire, cold drawn around the system after the use of quenching and tempering. Most than 15.0mm diameter wire is made by heating and winding process.
Different types of Shaped Spring Steel Wire have different production methods, common features are required to a certain strength, high toughness and good coil spring performance.
Commonly used in a variety of Shaped Spring Steel Wire production methods are as follows:
Threaded spring wire technology: (steel) wire rod - surface treatment - drawing (mattress wire can be used this method)
Lead quenched spring steel wire: wire rod size or cold drawn in the middle of the specifications for lead bath quenching, and then surface treatment and drawing.
Galvanized spring steel wire: usually in the finished product size for hot-dip or plating, but also the use of wire rods after hot-dip plating to the required size.
Oil quenching spring steel wire: according to the need can be used carbon steel or alloy steel, surface treatment and cold drawn to the finished product after the quenching and tempering treatment, this process in the car hanging spring and valve spring with more, ordinary Shaped Spring Steel Wire of course can also be used.
Surface treatment: the general use of pickling phosphate, remove the iron oxide skin, the formation of phosphate film; there are a few mechanical methods. The purpose is to meet the cold drawing process requirements, access to smooth surface. For the requirements of high fatigue life of the spring-Shaped Spring Steel Wire, such as valve-Shaped Spring Steel Wire, wire rods should be treated with peeled skin to reduce surface defects, if the steel can be carried out on the billet, but also help to reduce defects.
Drawing: The drawing process of the finished product has a great influence on the performance of the product. Generally, a large total reduction ratio of about 90% (see area reduction ratio) and a smaller pass rate (about 10% 20%) to ensure product toughness. For high-strength spring steel wire, pull the wire should be controlled when the outlet temperature of less than 150 ℃, to prevent the strain due to strain caused by torsional cracks, which is caused by the main defects of steel wire scrap. For this reason, the drawing must be well lubricated and adequately cooled, with a smaller pass reduction rate and drawing speed to help reduce the temperature rise of the wire.
Heat treatment: carbon steel spring steel wire commonly used lead bath quenching process, can be very small pearlite structure (sorbite), for improving the depth of drawing performance and shape spring wire performance are useful, lead bath alternative process fluidization Bed has not been promoted, only in some small diameter on the application. Alloy wire generally used annealing heat treatment, so that microstructure to adapt to the drawing deformation. The heat treatment of stainless steel wire is treated by solution treatment, and its purpose is to improve the organization to meet the needs of drawing. Oil quenching process used in the finished steel wire, the use of induction heating or gas, fuel heating furnace, the wire heated to the austenitizing temperature for a period of time, quenching and then a temperature tempering. Although the name is called oil quenching, are basically water quenching or high molecular weight water quenching