Die Forging Defects and Prevention of Liquid Modelparts
Die forging is the process of shaping metals by forcing them to deform between two opposing dies. In the forging process, pieces of metal are heated to temperatures of between 500-2200 °F(260-1205 °C) and then are work hardened by hammering or pressing them between the dies. This process improves the strength and toughness of the material being forged. The dies that are used in die forging are usually made of high-strength steel and are designed to produce the specific shape desired in the piece being forged.
Die forging is a precision process that requires close attention to detail to be successful. Defects can occur during the process, which can lead to reduced strength, higher scrap rates, and more expensive repair bills. Here are some common defects that can occur during die forging, and ways they can be prevented:
High Dimension Deviation: Die forging is a very precise process, and even slight imprecisions in the die design can lead to high variations in the final product. One way to prevent high dimension deviation is to ensure that each die is properly machined to the desired dimensional tolerances before use.
Non-Uniform Hardness: The work hardening of the material being forged must be done in a controlled manner to ensure uniform hardness throughout the piece. Non-uniform hardness can be prevented by properly heating the material when preparing it for forging, then using the hammer or press at the correct speed, pressure, and timing.
Non-Uniform Shrinkage: Heat-treating the piece being forged once it has been shaped is necessary to improve the physical characteristics of the material. Non-uniform shrinkage can occur if the heat-treatment process is not done properly, leading to an irregular shape. To prevent this, consistently monitoring the heat-treating process during forging is essential.
Porosity: Porosity is caused by trapped air or gases that are unable to escape during the forging process. porosity can weaken the overall strength of the forged piece. To prevent this, the die must be well-ventilated, and the pressure and speed of the hammer must be properly adjusted so that all trapped air is able to escape.
These are just a few of the potential defects that can occur during die forging. By properly designing and preparing the die, monitoring the forging process, and carefully heat-treating the piece after forging, these defects can be greatly reduced or eliminated. Quality control and careful oversight of die forging processes can help to ensure that the pieces being forged are of top-notch quality and ready for use.
