China's low-alloy steel Q345B - Encyclopedic - Shanghai Zhilian steel trade

Material Name: Q345B low-alloy steel
Materials are: steel
The major manufacturers: Other
Physical Properties: No relevant information
Availability hardness: no information
Typical applications: 1. Widely used in bridges, vehicles, ships, construction and pressure vessel.
2. For hot rolling, controlled rolling, normalizing, normalizing and quenching plus tempering state of supply and general structural steel works not less than 3mm thick steel plate, steel strip and steel, steel bar.

Related Description:. Overview

q345 is a steel material. It is a low alloy steel (c <0.2%), overall performance is good, low-temperature performance, Ling stamping performance, welding performance and good machinability. Widely used in bridges, vehicles, ships, construction and pressure vessel. q represents the yield of this material, behind the 345, the yield refers to the value of this material, in the 345 or so. As the material thickness will increase its yield value decreases. Similar to the naming method in q235.

q345a, q345b, q345c, q345d, q345e. This is a class distinction represents the main difference is the temperature of the impact of it! q345a level, is not to shock; q345b level is 20 degrees room temperature impact; q345c level, is 0 degree impact; q345d level, is the -20 degree impact; q345e level is -40 degrees impact. The impact of different temperatures, the impact of values are different.

In the plate, the case of low-alloy series. In the low alloy material, such material is the most common. q345 past way of talking to: 16mn.

II. Executive Standard:

q345 external implementation of the standards: gb709, the internal implementation of the standards: gb/t1591-94, the reasons for the implementation of standards, this plate allows the delivery of negative tolerance.

III. Q235 and q345 difference

Different: q235 yield strength of the lower limit 235mpa, q345 yield strength limit 345mpa (q for the Chinese characters meaning "bent" character, the latter values represent the lower limit of yield strength)

Two different alloy content: q235 for ordinary carbon steel, q345 low alloy steel. (Comparison with the old standard grade 1591-88 12mnv, 16mn 16mnre, 18nb, 14mnnb)

Properties and Applications

q235 - metal structure, the center intensity of less demanding or cyanide carburizing parts, bar, rod, hook, coupler, nut bolt, sleeve, shaft and welding parts.

q345 - good mechanical properties, low temperature performance can be, good ductility and weldability, used in low pressure vessels, tanks, vehicles, cranes, mining machinery, power stations, bridges and other structures to withstand dynamic load, mechanical parts, building structures general metal structure, use of hot-rolled or normalized condition, the following can be used to -40 ℃ cold regions of various structures.

Such as the structure is the strength of control, such as the structure is considered q345 stiffness control can be considered q235 q345 slightly more expensive price point, but because of its high strength, saving material. The specific choice of the above points from the comprehensive comparison.