Steel, including steel components, is tested for quality in a variety of ways, including tensile testing, bending fatigue testing, compression/bending testing and corrosion resistance testing. Materials and related products can be developed and produced in real time to keep track of product quality performance, which can avoid returns due to quality and waste of raw materials.
There are several common types of steel.
Carbon Steel
Carbon steel, also known as carbon steel, is an iron-carbon alloy with a carbon content (wc) of less than 2%. In addition to carbon, carbon steel generally contains a small amount of silicon, manganese, sulphur and phosphorus.
Carbon steel can be divided into three categories: carbon structural steel, carbon tool steel and free-cutting structural steel. Carbon structural steel can also be divided into two types of structural steel for construction and machine building.
According to the carbon content can be divided into low carbon steel (wc ≤ 0.25%), carbon steel (wc 0.25% ~ 0.6%) and high carbon steel (wc > 0.6%). According to the phosphorus, sulphur content can be divided into ordinary carbon steel (containing phosphorus, sulphur higher), high quality carbon steel (containing phosphorus, sulphur lower) and advanced quality steel (containing phosphorus, sulphur lower).
The higher the carbon content in general carbon steel, the higher the hardness and strength, but the plasticity is reduced.
Carbon structural steels
This type of steel mainly to ensure the mechanical properties, so its grade reflects its mechanical properties, with Q + numbers, where “Q” for the yield point “Qu” character of the Hanyu Pinyin initial, the number indicates the yield point value, for example, Q275 said yield point of 275MPa. If the grade is marked with the letters A, B, C, D, it means that the quality of the steel grade is different, containing the amount of S, P in order to reduce the amount of steel quality in order to improve. If the letter “F” is marked behind the grade, it is boiling steel, marked “b” for semi-sedentary steel, not marked “F” or “b” for sedentary steel. For example, Q235-A-F means A-grade boiling steel with a yield point of 235 MPa, and Q235-c means c-grade quiescent steel with a yield point of 235 MPa.
Carbon structural steels are normally used without heat treatment and in the supplied condition directly. Usually Q195, Q215 and Q235 steels have a low mass fraction of carbon, good welding properties, good plasticity and toughness, have a certain strength, and are often rolled into thin plates, bars, welded steel pipes, etc., used in bridges, buildings and other structures and in the manufacture of common rivets, screws, nuts and other parts. Q255 and Q275 steels have a slightly higher mass fraction of carbon, higher strength, better plasticity and toughness, can be welded, and are usually rolled They are usually rolled into sections, bars and plates for structural parts and for the manufacture of simple mechanical parts such as connecting rods, gears, couplings and pins.
Post time: Jan-31-2023