Home » Resources » How to Choose Plastic Injection Mould Steel?

How to Choose Plastic Injection Mould Steel?

How to reasonably choose plastic injection mould steel has been complicated system engineering, and also the key link of plastic injection mould making. It is an important work related to mould service life and plastic injection mould cost. In general, the material used to make plastic injection mould is required to have certain hardness and wear resistance at first. Secondly, it should have strength and toughness. The next is easy to machine. ACO Mold is professional injection moulding manufacturer which produce plastic injection mould and plastic parts.

Before selecting plastic injection mould steel, we firstly need understand the classification of mould. Mould is generally divided into 5 grades according to its’ service life:Injection mould
Grade 1: service life of mould is more than one million times.
Grade 2: Between five hundred thousand and one million times.
Grade 3: Between three hundred thousand and five hundred thousand times.
Grade 4: Between one hundred thousand and three hundred thousand times.
Grade 5: Below one hundred thousand times.

The plastic moulds for grade 1 and grade 2 is required to use the steel of it’s hardness is about HRC500. Otherwise, the mould is prone to wear. So the selected plastic injection mould steel not only has good heat treatment properties, but has good cutting performance under high hardness conditions.

Common used plastic injection mould material:
Here I only introduce the imported material common used by Chinese plastic injection mould manufacturer. Common used are: Swedish 8407, US S136 and 420&H13, and 2316&2344 and 083 of Europe.

In addition, the basic performance of steel need to be understand
1. Steel has sufficient surface hardness and wear resistance.
The surface roughness and dimensional accuracy of plastic parts, and the service life of plastic injection mould are all directly related to the hardness and wear resistance of mould surface, especially the forming surface of mould, such as the core and cavity of mould. Therefore, the forming surface of plastic injection mould is required to have sufficient hardness, and the hardenability can’t be lower than HRC55. For small plastic mould, the high-carbon and high-alloy steel can be chosen. For large plastic mould, the carburized steel can be selected, and perform heat treatment to be hardened to gain high wear resistance and extend mould service life.

2. Steel has sufficient strength and toughness.
Because plastic moulds, especially injection moulds withstand large moulding pressure during injection moulding, so the large and medium plastic injection mould or the plastic injection mould with complex cavity shape should have high strength and toughness to meet the usage performance requirement.

3. Steel has good machining performance.
Most of plastic moulds require perform a certain machining and bench work. In order to extend the service life of cutting tool, and improve the cutting performance and reduce the surface roughness, the plastic injection mould steel must have appropriate hardness to obtain the necessary precision and surface roughness.

4. Heat treatment deformation is small.
The plastic injection mould part usually is complicated in shape, and it is difficult to machine after quenching, even impossible to machine at all. Therefore, try to choose steel with small heat treatment deformation. In this way, the processing of plastic injection mould part can be reduced or no longer processed after heat treatment, which can guarantee the dimensional accuracy and surface quality requirements of plastic mould.

5. Have good corrosion resistance performance
Plastics and additives have chemical corrosive effect on steel surface. Therefore, the selected mould steel should have a certain corrosion resistance.

6. Have good polishing performance
In order to obtain smooth plastic parts, the surface roughness of mould cavity is required to be small, so the cavity must be polished to reduce the roughness of cavity surface. And the selected steel can’t have rough impurities and pores, and while polishing, pitting or orange peel defects can’t occur.

Welcome to ACO Mold injection moulding company and contact us. The mould engineers from ACO Mold will give you the best solution, and recommend the suitable materials for you. We are ready and looking forward to cooperate with your next project. You will be happy and satisfied to be our partner in mould making and injection moluding project.

Post a Comment:

Plz Calculate (3 - 9) =
(Your comment will show after approved.)

You may also like:

Online tour of our plastic injection mould making factory in Shenzhen China.
Featured Articles
How to Charge Fee When Modifying ... We all know that although product will make hand board for verification before development and it will not start the mould ...
How to Make Plastic Die Sinking ... Under the circumstance of without drawing, plastic injection moulding company can provide the product copy data service to make ...
Mould Maker, Injection Mould Making ... Mould Maker, Injection Mould Making Company Selection TipsIt is very easy to find an injection mould maker, the most simple and effective way is to participate in relevant exhibitions. ...
10 Factors Influence Injection Mould ... 10 Factors Influence Injection Mould QualitySteel is a decisive factor of mould quality, a reasonable choice of steel is the most important. Steel selection criteria are: ...
Basics of Plastic Injection Mould ... Basics of Plastic Injection Mould DesignCollect all basic technical documents from the mould design to finish processing, such as the mission statement, parts diagrams, ...