Hardware tools are usually made of steel, copper, and rubber
Steel: most of the hardware tools are made of steel
Copper: some riot tools use copper as a material
Rubber: some riot tools use rubber as material
If the chemical composition is divided, it can be summed up as two major categories of carbon steel and alloy steel.
It is divided into three categories: structural steel, tool steel and special performance steel.
According to the quality, the three types of ordinary steel, high quality steel and high quality steel are classified.
The carbon content of carbon steel under 1.5%, the carbon content of the steel is called "0.25% low carbon steel, 0.25% carbon steel is less than or equal to 0.6% between carbon steel, carbon steel and high carbon steel is more than 0.6%.
Because phosphorus and sulfur can increase the brittleness of steel at low temperature or high temperature, the content of phosphorus and sulfur in steel should be defined when the quality is classified. Ordinary steel, containing less than 0.045% sulfur content less than 0.055%. High quality steel, phosphorus content is less than 0.04%, the sulfur content of less than 0.045%. The sulfur content of tool steel, P = 0.04% respectively. In high-grade steel, phosphorus and sulfur content requirements were less than 0.03%.
Carbon structural steel is mainly used for manufacturing various engineering components (such as bridge, ship and building components) and machine parts, such as gears, shafts and connecting rods, etc., generally belonging to low carbon and medium carbon steel.
Carbon tool steel is the main language for making various tools, measuring tools, touching tools and hardware tools, generally belonging to high carbon steel. Carbon tool steel steel with "T", as T7 said carbon carbon alloy tool steel 0.7%. High quality carbon tool steel is represented by "A" after the number, such as "T7 A".
Class a steel. This kind of steel is supplied as a guarantee of mechanical properties. With a total of 1-7 grades, the greater the number of a steel, the greater the yield strength and tensile strength, but the smaller the elongation.
Class B steel, this kind of steel is supplied by chemical composition. With a total of 1-7 grades, the greater the number of the B steel, the higher the carbon content.
In order to improve mechanical properties, process properties, physical and chemical properties of steel, some alloying elements are added to steel during smelting, which is called alloy steel. The average carbon content of more than 1% alloy tool steel when the carbon content is not marked, the average carbon content is less than 1%, with very few said.
The total amount of the alloying elements in steel called < 5% low-alloy steel, 5% less than the total less than 10% alloy elements known as alloy steel, alloy elements called 10%, the total amount of high alloy steel.
Alloy steel can obtain mechanical properties that are difficult to achieve in carbon steel.
Chromium: increase the hardenability of steel and improve the wear resistance and increase the hardness.
Vanadium: it has a great contribution to improving the hardness, wear resistance and toughness of steel, especially for improving the wear resistance of steel.
Mo: it can improve the hardenability and tempering stability of the steel, refine the grain and improve the nonuniformity of carbides, thus improve the strength and toughness of the steel.
Steels used in hardware tools
Because of the special mechanical properties of the alloy tool steel, the alloy tool steel is usually used in the middle and high grade hardware tools. It is mainly applicable to the steam repair plant, automobile factory, power plant and industrial and mining enterprises which have high tool use rate and higher tool requirements.
Carbon tool steel is usually used in low grade hardware tools, which has the advantage of low price. It is mainly suitable for household users with low utilization rate and not high demand for tools.
S2 alloy steel (usually used for making screwdriver, screwdriver)
Cr Mo steel (commonly used to make screwdriver)
(usually used in the production of chrome vanadium steel sleeve, wrenches, pliers)
Carbon steel (usually used for making low grade tools)