Metallographic diagram of CK20 casting

CK20 is a high alloy tool steel developed for use in plastic injection molds and die-casting dies. It is a type of AISI (American Iron and Steel Institute) P20 steel. The addition of chromium and molybdenum to the steel give it hardenability and toughness, making it ideal for applications in the manufacturing and automotive industries.

The metal is drilled and hardened, and CK20-P20 steel requires post-heat treatment, also called austenitizing, for maximum hardness. The metal is first heated to about 844°C (1550°F) and then quenched in oil or water to form martensite. Martensite is a hard, durable, and brittle form of the metal, which is resistant to wear and tear.

The hardness of CK20-P20 steel can be measured using a Rockwell C (RC) scale. This scale measures relative hardness and is based on the depth of penetration of a diamond cone indenter into the material. On the Rockwell scale, a CK20-P20 steel that has been properly hardened has a hardness rating of 39-42 RC.

The composition of CK20-P20 steel is measured with a polarized light microscope, or PLM. The technique works by using a polarized light to highlight the metals in a sample. The microscope both identifies the different metals present in a sample and reveals the distribution of these metals in the powdered or cast form of the steel.

A metallographic analysis of CK20-P20 steel is done under a metallographic microscope. To do this, the sample is first embedded in an epoxy or plastic compound and then thinned by grinding. The thinned sample is then cut to a size suitable for viewing under the microscope, and then it is further polished and mounted on a hard, smooth surface.

To measure the nature of the microstructure of the sample, cross-sections are prepared. This is usually done by grinding and then polishing the sample thin. It is then mounted onto a microscope slide, and then cryofractured or electroplated with a gold finish before its microstructure can be viewed under the microscope.

Using a metallographic microscope, it is possible to view the microstructure of CK20-P20 at different magnifications. This will reveal details such as the size of grain boundaries, the texture of the grains, the size of large voids and the presence of inclusions such as impurities.

Overall, CK20-P20 steel is a high alloy tool steel that is highly valuable in manufacturing and automotive industries. It has excellent mechanical properties and wear resistance, as well as excellent cryogenic toughness. It is a versatile steel and can be used for a variety of applications. The analysis of the microstructure of the steel is essential in guaranteeing the steels performance and durability.

CK20 is a medium carbon low-alloy steel designed for diesel engine components such as rods, shafts, bushings, and other applications requiring high strength. The chemical composition of CK20 consists of 0.17%–0.23% carbon, 0.35%–0.45% manganese, 0.6%-1.3% chromium, 0.4%-0.7% silicon and 0.04%-0.1% molybdenum. CK20 steel has good machinability and excellent surface finish. It is a relatively tough material which makes it an ideal choice for engine components.

The metallographic structure of CK20 consists of ferrite, undissolved carbides, and small amounts of martensite as well as some retained austenite. The ferrite serves as a matrix and the undissolved carbides are distributed throughout it. The martensite structure is produced from the austenite during quenching, and the retained austenite is formed from incomplete martensite transformation. The martensite is more brittle and makes up about 0.5% of the total structure.

The graphite particles dispersed throughout CK20 are clear and well defined at the surface. The graphite is in a matrix of lighter and harder ferrite, exhibiting a transition from a coarser lower form to a finer upper form. The retained austenite is present in the form of complete lamellar or incomplete network structures with slight changes in diffraction angles.

Due to its excellent machinability, hardness and toughness, CK20 is suitable for components with complex shapes and load bearing materials. It can also be used for wear parts and components subjected to heavy loads. Because of its good machinability, it is easy to form into shapes with precise dimensions. It also has excellent surface finish, making it more attractive for components used in engine parts.