We owe the appearance of stainless steel to engineer Harry Brearley. By adding a chemical element called chromium to the metal, he tried to increase the melting point. This was required to improve the characteristics of artillery barrels. In the course of such experiments, it turned out that the resulting alloy has differences compared to others. They are chemical resistant. This is due to the formation of a chromium oxide film on the surface.
Research on stainless steel began in 1871, and the first patent was registered only in 1913. The modern analogue of stainless steel, which meets all the requirements for strength and chemical properties, was obtained in 1924 by a scientist named Hartfield.
Basic understanding of stainless steel
In directories or otherIn the literature, corrosion-resistant steel has the following designation: "steel grade 08X18H10". This means that it contains the following elements:
- carbon - no more than 0.8%;
- chrome - 18%;
- nickel - 10%.
These are the main chemical elements, but other inclusions are also present in the alloy, their percentage does not exceed 1%.
Main stainless steel products
Corrosion-resistant steel is used to make such high-quality products as:
- stainless wire;
- sheet steel;
- pipes of various wall thicknesses and internal diameters;
- profiled products.
Also, many household knives and food processor units are made from this material.
Stainless steel wire
Like any other metallurgy product, wire is produced in accordance with current Russian standards.
Regulates the production of such material as stainless wire, GOST 18143-72. According to this document, it has a thickness of 0.3 to 6 millimeters.
This wire can also be used as a final product and can be further processed by forming. Then from it you can get:
- chains with different link sizes,
- grid with different cell pitch,
- springs.
The cross section of such a wire is usually round, but oval or square types can also be found. The round section is very convenient forusing the material in the process of welding the same stainless steel.
Stainless wire has the following main advantages:
- high corrosion resistance to moisture, aggressive industrial environments and condensate;
- wire with a high content of molybdenum, chromium, nickel, copper, silicon, vanadium has high heat resistance, reliability and durability.
Use of stainless wire
Due to its long service life, resistance to acidic and alkaline environments, stainless steel wire has been widely used in two directions:
- knitting in ropes;
- welding;
- weaving mesh for filters.
Stainless wire, the price of which varies from 120 to 350 rubles per kilogram, depending on the thickness and features, is widely used in industries such as:
- machine-building;
- power industry;
- oil;
- chemical;
- food.
Welding wire
The broad development of the chemical industry required metallurgists to create a metal capable of maintaining high mechanical properties in aggressive environments. In addition to resistance to various chemical elements, some industries also require properties with which the metal can withstand the influence of high temperatures. Stainless steel solves many of these problems. In addition, no other material can be used in the food industry.
The modern level of processing of metal products makes it possible to produce complex products, but at the same time, welding joints cannot be dispensed with. Stainless wire is used for welding products in complex assemblies that are exposed to aggressive environments.
The main advantage that stainless welding wire has is that when it is used, the weld is practically clean, without harmful slags and parasitic inclusions. Thanks to the use of stainless steel material, the seam itself is not subject to oxidation. The price to pay for such advantages is that the welding process in this case is quite complicated, and consumables are expensive.
Stainless steel wire is used only in automatic welding. It is supplied by an automatic feeder, and current is passed through it.
A protective gas enters the arc zone, which displaces oxidizing agents, due to this, the seam is completely cut through and all components are connected.
Welding wire is wound into a steel drum with a continuous length of up to 50 meters. The average diameter of the drum is 50 millimeters. The wire is fed from the spindle by the rotation of two clamping coils. Oblique grooves are cut in the middle, with the help of which the wire is reliably captured and fed to the welding gun. Before winding stainless wire, it is thoroughly cleaned of dirt and foreign matter.
Welding wire marking
Wire is madecold rolling and hot working. It has two types of accuracy - normal and increased. In the latter case, after the marking, the letter P is placed in brackets.
Stainless wire has two main markings - domestic and foreign.
Russian marking has an alphanumeric form - 10X17H13M2T. The following order of letters and numbers means its internal structure and chemical composition. The numbers determine the percentage composition of a particular element, and the letter - the element itself. The above abbreviation stands for:
- 0, 1% carbon;
- chrome - 17%;
- nickel - 13%
- manganese - 2%
- letter T means that the wire is produced by heat treatment.
The European standard is quite complicated and does not have a single marking according to the norms. Each steel manufacturer patents its composition.
