What are the possible consequences of material performance problems during mold processing?

In the process of mold processing, material performance problems may lead to a series of consequences in processing links, mold use stages and product molding, as follows:

Processing link

Increased processing difficulty: if the hardness of the material is high, the tool wear will be aggravated, and even the tool edge will collapse, which will increase the processing cost and processing time. For example, when milling high hardness die steel, the service life of cemented carbide tools will be obviously shortened. However, uneven hardness of materials will lead to unstable cutting force during machining, which will affect machining accuracy and surface quality, and lead to problems such as dimensional deviation and poor surface roughness.

Increased processing defects: There are defects in the material, such as air holes and sand holes, which may be exposed during processing, forming surface pits, cracks and other defects. At the same time, the toughness of the material is not good, and problems such as edge collapse and corner drop are easy to occur during processing, which affects the appearance and dimensional accuracy of the die.

Mold use stage

Wear resistance reduction: insufficient hardness or uneven structure of die materials will reduce its wear resistance. In the frequent stamping, injection molding and other molding processes, the mold surface is prone to wear and strain, which leads to the shortened service life of the mold and the increased maintenance cost. For example, after long-term friction with plastic melt, if the wear resistance is not enough, there will be wear marks, which will affect the surface quality of plastic parts.

Insufficient strength and toughness: the material strength is not enough, and the mold is prone to deformation, cracking and other failure forms when it is subjected to large forming pressure. For example, in the process of high pressure casting, if the material strength is insufficient, the die cavity may be deformed because it can't bear the pressure of die casting. If the toughness of the material is poor, the mold is prone to brittle fracture under impact load, which affects the normal use of the mold.

Decline in corrosion resistance: for some molds used in corrosive environment, such as plastic molds, if the corrosion resistance of mold materials is not good, the mold surface will rust and corrode, which will affect the accuracy and surface quality of the mold and shorten the service life of the mold.

Product molding

The dimensional accuracy of the product is affected: the deformation of the mold material due to performance problems will be directly transferred to the molded product, resulting in the dimensional deviation of the product beyond the tolerance range. For example, the core or cavity of an injection mold is deformed by heat during the injection process due to the large thermal expansion coefficient of the material, which will affect the dimensional accuracy of the injection parts.

Surface quality deterioration of products: the surface quality and performance of mold materials will directly affect the surface quality of products. If there are defects or poor wear resistance on the surface of the mold material, these defects will be copied to the surface of the product during the molding process, resulting in scratches, pits and inconsistent gloss on the surface of the product. For example, after the surface of the stamping die is worn, the surface of the stamped parts will show signs of strain.

Product forming defects: material performance problems may also lead to some abnormal conditions in the molding process of the mold, which will further affect the molding quality of the product. For example, the uneven thermal conductivity of mold materials will lead to uneven temperature distribution in the molding process, resulting in uneven cooling, deformation, shrinkage marks and other defects of products.