Hot half molds play a crucial role in industrial production, especially in molding processes such as injection molding. However, long-term use may lead to mold damage due to thermal fatigue, which not only affects product quality but also increases production costs. In order to effectively prevent damage to the hot half mold due to thermal fatigue, it is necessary to start from multiple aspects.

In the selection of mold materials, materials with high thermal fatigue resistance should be chosen. For example, hot work die steel is an ideal material with good thermal stability and toughness. This material can withstand repeated heating and cooling processes, reducing cracks caused by thermal stress. At the same time, appropriate heat treatment of materials is also important. Through reasonable quenching and tempering processes, the grain size can be refined, the strength and toughness of the material can be improved, and its resistance to thermal fatigue can be enhanced.

The design structure of molds also has a profound impact on preventing thermal fatigue. Optimize the wall thickness design of the mold to avoid significant differences in wall thickness. Uneven wall thickness can lead to inconsistent heat conduction, resulting in significant thermal stress during the cooling process. Whenever possible, try to design the cooling channels of the mold more reasonably to ensure even cooling of all parts of the mold. For example, a conformal cooling channel can be used to allow the cooling medium to be close to the surface of the mold cavity, effectively removing heat and reducing local overheating.

Controlling the heating and cooling rates is crucial during the use of the hot half mold. Avoid rapid heating or cooling, as this can create a large temperature gradient inside the mold, leading to thermal stress. For example, in the cooling stage after the injection molding process is completed, an appropriate cooling rate should be adopted, and excessive cooling should not be used in a hurry to demold. At the same time, the working temperature range of the mold should be strictly controlled. By installing temperature sensors and controllers, the working temperature of the mold is stabilized within a reasonable range to prevent severe temperature fluctuations.

In addition, regular maintenance is also key to preventing thermal fatigue damage. Regularly inspect the surface of the mold for defects such as cracks and corrosion. For some small cracks, appropriate repair techniques such as laser cladding can be used for repair. And the cooling channel should be cleaned to prevent the accumulation of impurities such as scale from affecting the cooling effect.

Through various measures such as material selection, design optimization, usage control, and maintenance, it is possible to effectively prevent damage to the hot half mold due to thermal fatigue, extend its service life, and ensure the smooth progress of industrial production.