The reasons for insufficient hardness and uneven hardness in plastic mold processing are mainly as follows:
I. Raw material aspects
Steel quality issues: If the selected mold steel itself does not meet the hardness standard, or there are problems such as uneven composition and excessive impurities in the steel, it will lead to insufficient hardness or uneven hardness of the processed mold.
Improper heat treatment of materials: If the heat treatment process of steel is not well controlled, such as unreasonable parameters of quenching temperature, time, and cooling rate, the steel will not be fully hardened, resulting in insufficient hardness. At the same time, uneven heating and cooling will also lead to uneven hardness.
II. Processing aspects
Unreasonable processing technology: For example, improper selection of cutting parameters. Excessive cutting speed and feed rate may cause excessive heat on the mold surface and affect hardness.
Influence of electrical discharge machining: After electrical discharge machining, a 变质 layer will be formed on the mold surface. If not properly treated, the hardness will be reduced and uneven.
Machining stress: If the stress generated during the processing process is not eliminated in time, it may affect the hardness uniformity of the mold.
III. Design factors
Complex mold structure: A complex mold structure may lead to uneven heat distribution during the heat treatment process, thereby causing uneven hardness.
Unreasonable cooling system design: Uneven cooling will affect the hardness uniformity of the mold, especially during the quenching process.
IV. Other factors
Detection error: Inaccurate hardness detection methods or inappropriate detection locations may create the illusion of insufficient hardness or uneven hardness.
Environmental factors: Environmental temperature, humidity and other factors during processing and heat treatment may also have a certain impact on the hardness of the mold.
