A pressure processing method in which the metal blank passes through the gap between a pair of rotating rolling rollers (in various shapes) and is compressed by the rolling rollers to reduce the cross-section and increase the length of the material.

It is the most commonly used production method for producing steel and is mainly used to produce profiles, plates, and pipes. Divided into cold rolling and hot rolling.

A pressure processing method that uses the reciprocating impact of a forging hammer or the pressure of a press to change the blank into the required shape and size.

It is often used to produce materials with larger cross-sections such as large materials.

It is a processing method that draws the rolled metal blank (shaped, tube, product, etc.) through the die hole into a reduced cross-section and increased length.

It is mostly used for cold processing.

It is a processing method in which metal is placed in a closed extrusion cylinder and pressure is applied on one end to extrude the metal from a prescribed die hole to obtain finished products of different shapes and sizes.

It is mostly used in the production of non-ferrous metal materials.

Carbon steel

alloy steel

structural steel

tool steel

Special performance steel

Classification by smelting method

According to the degree of deoxidation

Ordinary steel

High quality steel

Advanced quality steel

Non-metal protective layer

metal protective layer

Tensile properties

Plasticity

Impact toughness

Fatigue resistance

hardness

Cold bending performance

Weldability: refers to whether the steel is suitable for common welding methods and processes. The weldability of steel is affected by its chemical composition and content.

High carbon content, high sulfur content, high phosphorus content, etc. will reduce weldability. Carbon steel with a carbon content of less than 0.25% has good weldability.

1. Cold working and strengthening treatment

2. Timeliness

Carbon is the most important element that determines the properties of steel

When the carbon content in steel is below 0.8%, as the carbon content increases, the strength and hardness of the steel increase, while the plasticity and toughness decrease;

However, when the carbon content is above 1.0%, the strength of the steel decreases as the carbon content increases.

As the carbon content increases, the welding performance of steel becomes worse, the cold brittleness and aging sensitivity increase, and the atmospheric corrosion resistance decreases.

Cold brittleness - refers to the phenomenon that the impact value of metal materials is significantly reduced at low temperatures.

Thermal brittleness - refers to the phenomenon that the impact value of certain steel materials at room temperature drops significantly after staying in the temperature range of 400 to 500°C for a long time.

Silicon is a beneficial element in steel. When its content is controlled to <1.0%, the strength of steel can be improved without significant impact on plasticity and toughness.

Manganese, as a beneficial element in steel, is the main alloying element in low-alloy structural steel in my country.

Manganese has strong deoxidation and desulfurization capabilities, which can eliminate or reduce the thermal brittleness caused by oxygen and sulfur, greatly improve the hot processing performance of steel, and at the same time increase the strength and hardness of steel.

Sulfur is a harmful element in steel.

The presence of sulfur will increase the thermal brittleness of steel, reduce various mechanical properties of steel, and also reduce the weldability, impact toughness, fatigue resistance and corrosion resistance of steel.

Phosphorus is a harmful element in steel.

As the phosphorus content increases, the strength, yield-to-strength ratio, and hardness of steel increase, while the plasticity and toughness decrease significantly. Significantly increases the cold brittleness of steel.

Phosphorus also significantly reduces the weldability of steel.

But phosphorus can improve the wear resistance and corrosion resistance of steel.

Oxygen is a harmful element in steel.

As the oxygen content increases, the strength of steel increases, but the plasticity, especially toughness, decreases significantly, and the weldability becomes worse.

The presence of oxygen can cause thermal brittleness of steel.

As the nitrogen content increases, the strength of the steel can be increased, the plasticity, especially the toughness, is significantly reduced, the weldability becomes worse, and the cold brittleness intensifies.

Titanium can significantly increase strength, improve toughness and weldability, but slightly reduce plasticity.

Adding it to steel can weaken the adverse effects of carbon and nitrogen and effectively increase the strength, but it will also increase the tendency of welding to be brittle and hard.