Hot Forging Vs. Cold Forging

Hot Forging Vs. Cold Forging

Metal forging is one of the techniques widely used in the production of industrial machine tools. The technique promotes production of tools that have incredibly high strength tools. There are two types of metal forging or metal forming and both deliver similar results. They include hot forging and cold forging. But choosing the best types for a particular application between the two options depend on a number of criteria. In this piece, we are going to look at these two types of metal forming processes and where each excels the best.

The Hot Forging Process

As the name suggests, hot forming is the process by which the material is heated to be formed. Hot forging uses varying temperatures depending on the type of metallic material. Here the 3 average temperatures used for the hot forging:

  • 360°C to 520°C for Al-Alloys
  • 700°C to 800°C for Cu-alloys
  • Up to 1150°C for steel

Hot forging works by raising the temperature of the metal above the crystallization point.  The extreme heating is molten the metal hence avoiding strain hardening of the metal during deformation. However, oxidation is a challenge during this process. However, Isothermal forging is a method of hot forming that address the problem of oxidation. With this method, the process of forming tools occurs in a highly controlled atmosphere space or a vacuum. Similarly, you can look for other ways to reduce the level of oxidation.

Main Consideration for Hot Forging

Hot forging is common for the production of tools and wear parts with greater influence in the technical arena. However, it is common with metals that features a high formability ratio. Here are other key considerations for hot forging:

  • Low medium accuracy
  • Homogenized grain structure
  • Increased ductility
  • Production of discrete wear parts and tools

Advantages Associated With Hot Forging

  • Less precision tolerance
  • Varying grain structures
  • The material could warp while cooling

Cold Forging

Cold forming, also known as cold heading, is the opposite of the hot forging. The process deforms metal while it is below its crystallization point. The process is usually used common for producing soft metals such as aluminum but can also work with hard metal such as steel. However, cold forging is popular since its cost effective compared to hot forging. In most cases, it does not require finishing. In addition, cold forged tools can be heat treated for higher strength.

Cold Forging Process

The cold forging process occurs at near room temperature. Carbon or standard alloys steels are the most common metals for cold forging. There are various cold forming methods used, but impression-forging is the most common.  During this process, the metal to be deformed is placed into the carbide die attached to an anvil. The metal is struck multiple times rapidly until the desired product is formed.

Benefits of Cold Forging

There are numerous benefits that comes with cold forming. One of the main benefits of this process is that it does not require finishing hence its popularity. In addition, it uses less energy. Here are other benefits of cold heading:

  • Handles high die loads
  • Enhanced reproducibility
  • Improved dimensional control
  • Easier to impart directional properties

Limitations of Cold Forging

  • You must clean the metal f first.
  • The metal could be less ductile
  • Requires strong tooling
  • Residual stress could occur

However, of the two metal forging processes excels in different conditions but the results are the same. At wear parts of China, we produce our wear parts and tools using the two methods. That is the reason why the quality of our products have been astounding. In addition to producing, wear parts China provides external processing services for hot forging and cold forging. Feel free to contact us any time or visit our factory.