How does an injection mold factory select materials for injection molds?

The injection mold factory needs to determine the materials used in the various parts of the injection mold before the production of the injection mold. The injection mold is generally composed of an inner mold, a mold base, a guide post, a guide sleeve, a bush, a push rod, a thimble, Composed of pull rods and various other board materials, in actual production, the injection mold factory will select suitable materials according to the actual needs of different parts, and control the production cost to the greatest extent on the basis of ensuring quality.

Inner mold parts: mainly refer to mold cores, sliders, inclined tops, inserts, etc. For injection molds without any requirements, 45 steel and 50 steel materials are generally used; for ordinary requirements, P20 pre-hardened plastics are generally used Mold steel; for high-demand injection molds, 718 super pre-hardened plastic mold steel must be selected; for very strict precision injection molds, 738 (4Cr2NiMnMo national standard) steel must be selected; if the customer has polished injection molds The demand for mirror gloss, most injection mold factories will choose NAK80 mirror plastic mold steel; in the process of using injection molds to produce plastic products, corrosive gases are sometimes generated, then we need to choose corrosion-resistant mold steel To produce, generally such as M300 corrosion-resistant steel.

Mold base: Generally, the minimum required mold base is 45 steel; the commonly used mold base material is mostly 50 steel; for injection mold mold bases with certain requirements, 55 mold steel is selected; For the most exquisite injection molds, GS638 (P20 American standard GS638 German standard 42CrMo national standard) mold steel must be selected to meet the requirements of use.

Guide post: 1, 20# (S20C) or 20Mn2B (SMn420), treatment: carburizing and quenching, the hardness after treatment is greater than or equal to 55HRC 2, T8A, T10A, treatment: surface quenching, the hardness after treatment is less than or equal to 55HRC 3. 45# treatment : Quenching and tempering, surface quenching, low temperature tempering, the hardness after treatment is greater than or equal to 55HRC

Guide sleeve: Most injection mold factories use H62 brass or bronze alloy to make guide sleeves.

Bushing: Most of the bushing mold factories choose 45#, 50#, 55# Treatment: surface quenching, the hardness is greater than or equal to 55HRC.

Push rod, thimble, pull rod: T8, T8A, T10, T10A Treatment: quenching, low temperature tempering, hardness greater than or equal to 55HRC45#, 50#, 55# Treatment: quenching, hardness greater than or equal to 45HRC.

Various plate materials: General injection mold factories choose to use 45#, 50#, 40Cr (quenched and tempered), structural steel Q235~Q275, if you encounter the need to produce large plates, you can choose to use ductile iron instead.

We will be happy to hear your thoughts

Leave a reply


Need Help?

I’m Here To Assist You

How to make a perfect plastic injection mold and injection molding is always our goal.