Industry information

How to choose plastic mold steel

2021-06-29

How to choose plastic mold steel

The selection of plastic die steel should be based on the type of plastic that is molded, the shape, size, precision and quality of plastic products that are molded

Quantity and quantity of different requirements, at the same time to consider the manufacturing mold conditions and processing methods, the selection of different types of steel, such as seepage

Carbon steel, quenching and tempering steel, high carbon tool steel, corrosion resistant steel, low carbon maraging steel, etc


1 .how to choose plastic mold steel - carburizing steel

The carbon content of the carburizing steel is generally within the range of 0.1%~0.25%, and the hardness of the annealing state is low, and it has good cutting performance

Good plasticity, can be made by cold extrusion molding method.Carburizing after quenching, low temperature tempering treatment, die surface with

With high hardness, high wear resistance and polishing, and a certain strength and toughness, so as to ensure the use of the mold and effective

To improve the service life of the mold.Due to the

Common carburizing steel has carbon low carbon steel 10, 20 steel and alloy low carbon steel 20Cr, 12CrNi2, 12CrNi3A, etc.

Because of its poor hardenability, carbon low carbon steel is only suitable for the mold with small load and low requirement.Low carbon alloy

Compared with carbon low carbon steel, steel has better hardenability, so it is suitable for making plastic molds with larger sections and larger loads.

Due to the limitation of long cycle, carburizing equipment and batch, the use of carburizing steel is seldom used.

2.How to choose plastic mold steel - tempered steel

The quenching and tempering steel used for the plastic mold is medium carbon steel such as 45, 55 steel and carbon steel and 4Cr, 3Cr2Mo, 5CrNiMo,

4Cr5, MoSIN1 and other alloy steels.

Plastic molds are made from tempered and tempered steel, roughed in the annealed state, then tempered and tempered, and finally finished.

Or after quenching and tempering or normalizing treatment, direct rough machining and finishing, to avoid or reduce the deformation of the mold during heat treatment

And cracks and other defects.

Carbon quenched and tempered steel 45 is a commonly used plastic die steel, has good cutting performance, but because of its poor hardenability, tempering

After the strength and hardness is low, the more suitable hardness is HRC33~38, so it is only suitable for small or small batch production of plastics

The mould

For the production of plastic products in large batch, complex cavity of medium or large plastic mold, it is appropriate to use alloy tempered steel.this

The hardness of class steel is HRC42~48 after pre - hardening treatment.

3.How to choose plastic mold steel - high carbon tool steel

High carbon tool steels, such as Cr12, Cr12MoV, Cr WMn, 9Mn2V, etc. have high hardness after quenching and tempering at low temperature

And high wear resistance.Therefore, it is often used in the manufacture of thermosetting plastic molds or wear-resistant thermoplastics (such as thermoplastics reinforced by glass fiber) molds.The suitable hardness of this kind of steel after heat treatment is HRC58~60.

4.How to choose plastic mould steel - corrosion resistant steel

Corrosion resistance of corrosion resistant steel is mainly related to its chemical composition. Corrosion resistant steel is basically a stainless steel with high chromium content.With resistance to

The surface of the etched steel processing die need not be chrome plated.The commonly used corrosion resistant steel is 4Cr13, 9Cr18, 9CrL8MoV, Cr14Mo,

Cr14Mo4V martensitic stainless steel.

5.How to choose plastic mold steel - maraging steel

Maraging steels are ultra-low carbon and ultra-high strength steels.Ultra-low carbon maraging steel has good workability, weldability,

Corrosion resistance and mirror processability.The hardness of maraging steel in solution state is HRC30~35, and aged at 480 for 3~6h

After aging, the hardness can reach above HRC50 and the deformation is very small during aging.Therefore, maraging steels are used

In order to obtain the required hardness and strength of the mould, the mould can be made by mechanical processing in the state of solid solution and then aging treatment

Degrees.Maraging steel is suitable for the manufacture of large and complex plastic molds with high precision, wear resistance and corrosion resistance.