The difference between carbon steel stainless steel

It mainly refers to the steel whose mechanical properties depend on the carbon content in the steel,  generally does  add a large amount of alloying elements,  is sometimes called ordinary carbon steel  carbon steel.

Carbon steel is also called carbon steel, which refers to an iron-carbon alloy with a carbon content of less than 2% WC.

In addition to carbon, carbon steel generally contains a small amount of silicon, manganese, sulfur,  phosphorus.

According to the purpose, carbon steel can be divided into three categories: carbon structural steel, carbon tool steel  free-cutting structural steel. Carbon structural steel is further divided into two types: building structural steel  machine manufacturing structural steel;

According to the smelting method, it can be divided into open hearth steel, converter steel  electric furnace steel;

According to the deoxidation method, it can be divided into boiling steel (F), killed steel (Z), semi-killed steel (b)  special killed steel (TZ);

According to the carbon content, carbon steel can be divided into low carbon steel (WC ≤ 0.25%), medium carbon steel (WC0.25%-0.6%)  high carbon steel (WC>0.6%);

Generally, the higher the carbon content in carbon steel, the greater the hardness  the higher the strength, but the lower the plasticity.

Stainless  acid-resistant steel is referred to as stainless steel. It is composed of two parts: stainless steel  acid-resistant steel. In short, the steel that can resist atmospheric corrosion is called stainless steel,  the steel that can resist chemical medium corrosion is called acid-resistant steel. Stainless steel is a high-alloy steel with more than 60% iron as the matrix  alloying elements such as chromium, nickel  molybdenum added.

When the chromium content in the steel exceeds 12%, the steel is  easy to corrode  rust in the air  dilute nitric acid. The reason is that chromium can form a very tight chromium oxide film on the steel surface, which effectively protects the steel  corrosion. The chromium content in stainless steel is generally more than 14%, but stainless steel is  without rust. In coastal areas  some places with severe air pollution, when the chloride ion content in the air is large, there may be some rust spots on the surface of stainless steel exposed to the atmosphere, but these rust spots are limited to the surface  will  corrode the internal matrix of the stainless steel.

Generally speaking, steel with a content of Wcr greater than 12% has the characteristics of stainless steel. Stainless steel can be divided into five categories according to the microstructure after heat treatment: ferritic stainless steel, martensitic stainless steel,  austenitic stainless steel. , Austenitic-ferritic stainless steel  precipitation carbide stainless steel.

Stainless steel is usually divided into:

1. Ferritic stainless steel. Chromium 12% to 30%. Its corrosion resistance, toughness  weldability increase with the increase of chromium content,  its resistance to chloride stress corrosion is better than other types of stainless steel.

2. Austenitic stainless steel. It contains more than 18% chromium, about 8% nickel  a small amount of molybdenum, titanium, nitrogen  other elements. It has good comprehensive performance  is resistant to corrosion by various media.

3. Austenitic-ferritic duplex stainless steel. It has the advantages of both austenitic  ferritic stainless steels,  has superplasticity.

4. Martensitic stainless steel. High strength, but poor plasticity  weldability.