Cr12 (all through vacuum smelting and casting) metallographic diagram

讲述Cr12金相图

Cr12 (also known as D2 tool steel) is an air-hardened cold-work tool steel that provides excellent toughness and wear-resistance properties. Due to its high carbon content, Cr12 steel is extremely strong and hard, making it ideal for use in applications that require high-performance wear-resistant tools. Being a premium grade tool steel, it is typically vacuum-cast or remelted for improved purity.

The appearance of Cr12 steel is typically shiny and dark gray, however it can have variations in color due to the presence of different elements, such as vanadium and chromium. Its unique combination of hard wearing elements makes it a great choice for tooling materials, and its properties are typically represented in a microstructural phase diagram. This is known as the ‘Cr12 gold diagram.

The gold diagram visually displays the composition of Cr12 steel in both its solid and liquid states. It consists of four different areas that represent its different properties. From left to right, the areas are: austenite, ferrite, pearlite and martensite. What’s more, the diagram shows the amount of each element by weight in the steel.

Austenite is the most common form of Cr12 and is predominantly composed of iron and carbon. This is the form the steel takes when it melts, and is present during the quench tempering process.

Ferrite is the second most common form of Cr12 and is composed of small amounts of iron and carbides. It can be detected in the liquid state and can remain until the steel is at room temperature.

Pearlite is a combination of ferrite and cementite, which is the result of a partially decomposed austenite. It is formed during the quench tempering process and is identifiable by the small crystals it forms.

Finally, martensite is the most resistant form of Cr12 and has the highest hardness. It is composed of iron, carbon and some cobalt, and is present until the steel has cooled to room temperature.

Overall, the Cr12 gold diagram provides a comprehensive visual description of the alloy’s properties. By understanding the properties of Cr12 steel, one can make better informed decisions when choosing a steel for a particular job. For instance, knowing the type of steel and its thermal properties can help guide a machining process. As such, an understanding of the Cr12 gold diagram is invaluable in the metalworking industry.

Cr12(D2, 1.4C- 12.5Cr), a common tool steel, is made with vacuum degassing and several other steps to make tool-level quality from high purity iron and chromium. Tools made from this material are generally in demand due to its strength and wear resistance.

This steel’s main alloying elements are carbon and chromium, which gives it its strength. The addition of chromium also helps to create a layer of chromium oxide on the surface of the steel, providing further protection against corrosion and increasing wear resistance.

Metallographic inspection of the steel reveals it has a martensitic matrix. Martensitic stainless steel usually contains ferrite and carbides, but they can be eliminated during processing due to the vacuum degassing.

The grain size is mostly fine. The average grain size is generally in the range of 3-8 microns. The presence of carbides and/or nitrides have been reported as well, depending on the processing of the steel and the specific product.

The surface of the steel is generally smooth and free of defects, indicating good control of the thermomechanical processing used in the production.

In conclusion, Cr12(D2, 1.4C- 12.5Cr) tool steel is a strong and wear-resistant steel that can provide various benefits to any tools or products that it is used in. Its main alloying elements are carbon and chromium, and it undergoes a thorough thermomechanical process to ensure its quality. Its Martensitic matrix and fine grain size provide excellent properties to the steel and make it suitable for use in many industrial applications.